X swad science

MAHARASHTRA STATE BOARD OF SECONDARYAND HIGHER SECONDARY EDUCATION

SHIVAJINAGAR, PUNE-411 005

SECONDARY SCHOOL CERTIFICATE EXAMINATION(STD-X)

SELF-STUDY BOOKLET FORPRIVATE CANDIDATES

SCIENCE AND TECHNOLOGYPART - I AND II

(ENGLISH MEDIUM)

MAHARASHTRA STATE BOARD OF SECONDARYAND HIGHER SECONDARY EDUCATION


SECONDARY SCHOOL CERTIFICATE EXAMINATION(STD-X)

SELF-STUDY BOOKLET FORPRIVATE CANDIDATES

SCIENCE AND TECHNOLOGYPART - I AND II

(ENGLISH MEDIUM)

N.B.

Exercise section - Page nos. 86 to 202 should be solved and is to besubmitted at the centre as per instructions of the Head of the Centre.

(iii)

Introductory

About the Booklet

This booklet is specially prepared for you by experienced teachers. The booklet

has two sections.

Section I consists of summary of the chapter. It includes important points from

the chapters. It also includes some tips, instructions in between and some solved

examples.

Section II consists of exercises for self study. They involve important questions

from your textbooks and also some additional exercises for practice.

How to use the booklet ?1. The booklet consists of summary of each chapter from the textbook. But it

includes only some important points to bring to your notice. So do not rely

merely on the summary given. Read the complete chapter from the textbook

before studying the summary.

2. Try to understand the concepts and principles given in the summary. If you

do not understand, refer to the chapter in the textbook once again.

3. Study figures, diagrams, graphs, tables from the textbook. They are not

included in the booklet.

4. Study the solved sample questions or examples. Try to concentrate on the

format of answers sequence of the points included and steps of solving

numerical examples carefully.

5. Once you become confident enough, be ready to solve the exercises given

in section II of the booklet.

6. Try to write answers and solve examples on your own. In case of difficulty,

refer to page numbers from the textbook given against each question. Re -

read the content, organise your answer and write it down.

7. Study the written answers till you master them.

Some tips for self study - Concentrate while studying. Sit erect. Avoid noise around as far as possible.

Try to understand the meaning of scientific terms used. This will help you to

remember them.

Pay more attention to highlighted words / statements in the textbook. Read

(iv)

aloud that part, if required.

Try to comprehend the definitions, formulae and equations. Write them again

and again till you learn them by heart.

Study solved examples. Try solving them without seeing and check to get

self feedback. Find similar examples from the textbook and solve them.

Seek guidance from peer group and teachers available in case of difficulty.

Practice drawing diagrams. Remember labels given to parts and structure.

You may find some chapters easy and some chapters difficult according to

your interest. So start from easy chapters and slowly go to the difficult one.

Remember the chapters are not difficult. Only thing is you probably do not

understand them. Make effort to understand them. Do not skip any chapter.

The success is yours !

Self Study Booklet (English Medium) (1) Science and Technology Part I & II

Part- 1 Self Study MaterialChapter 1

Classification of Elements(Marks - 5, Marks with option 8)

Introduction :Man has discovered 116 elements uptil now. We use (Modern Periodic Table,

(Long Form of Periodic Table) prepared by Moseley to study the elements.Features of Modern Periodic Table :(1) Atomic number of an element is equal to the number of protons or electrons in the

atom of the element.(Atom of any element contains equal number of protons and electrons)

(2) Moseley observed that properties of the elements are a periodic function of theiratomic numbers. Therefore Moseley assumed atomic number (z) as the basis ofmodern periodic table.(Definition of the periodic law-refer to page 2)

(3) There are 7 rows (known as periods) and 18 columns (known as Groups)(4) At the bottom of the periodic table there are 2 additional rows known as series. All

the elements in series belong to third group. Do not misunderstand series asperiods.

(5) Place of element in the periodic table suggests -a) Serial No. of periodb) Whether the element is metal, non-metal or inert gas.c) reactivity of an elementd) Valency of an elemente) no. of electrons in the outermost orbit.f) While studying periods, one has to refer the periodic table from left to right

gradually. One can understand whether the element is metal, non-metal,metalloid or an inert gas.

g) Refer the group from top to bottom. No. of shells go on increasing from top tobottom gradually. All the elements from the same column contains equalnumber of electrons in the outermost shell.

h) The entire table is divided into four blocks based on electronic configuration ofelements.

Block Group No. Name

s block 1,2 Normal elementsp block 13 to 17 Normal elementsp block 18 Inert elementsd block 3 to 12 Transition elementsf block lanthenide, Inner transition

actinide series elements

Pc-2/d/Delight/D1 to D5/ Science & Tecg, P1/Std.X science & tech. p1-D1 ok A


The periodic table can be read like a cross-word puzzle.Prepare a blank periodic table and solve the following.

Ex. 1 : The element carbon (C) is in second period and 14th group of the periodic table.Place element Carbon in the proper place.

Ex. 2 : Atomic no. of hydrogen is 1and that of lithium is 3. Place the elements in properplace in the periodic table. (Note - Electronic configuration of hydrogen is 1, andlithium is 2,1)

2 3 4 5 6 71

periods

1/IA

2/IIA

s-bl

ock

Mo

der

n P

erio

dic

Tab

le

Tra

nsiti

on e

lem

ents

(M

etal

s)

d-bl

ock

3 IIIB

4 IVB

5 VB

6 VIB

7V

IIB8

9 VIII

1011 IB

12 IIB

13 IIIA

14 IVA

15 VA

16 VIA

17 VIIA

p-bl

ock

(Nor

mal

ele

men

ts)

5 B6 C 14 S 32 G

e33 A

s

51 Sb

52 Te 84 Po85 A

t* *

serie

s -

1 *

serie

s -

2 *

No.

of

Ele

men

ts -

per

iod

- fir

st =

2,

perio

d se

cond

= 8

perio

d th

ird =

8,

perio

d fo

urth

= 1

8, p

erio

d fif

th =

18

perio

d si

xth

= 3

2,pe

riod

seve

nth

= 3

0The

bor

derin

g el

emen

ts a

long

the

zig

-zag

lin

ear

e th

e M

etal

loid

s

f-blo

ck

Ele

men

ts:

z sy

mbo

l(E

lect

roni

c co

nfig

urat

ion)

18/

zero


Ex. 3 : Atomic no. of silicon is 14, which is greater than atomic no. of carbon by 8. Locatethe position of silicon in the periodic table, with the help of given information.

Prepare a blank table (Table no. 1.2, page 4)If we consider the table from left to right, we can observe that the chemicalproperties of elements change gradually. Table no. 1.2 consists of the molecularformulae of compounds formed by elements of the second period. The change invalency depends upon the change in electronic configuration of elements. Gradualchange in the molecular fourmulae is synchronous with the change in properties ofelements. While filling Table no. 1.2, first write symbol and valency of the element.After that write molecular formula of the corresponding compound.e.g. LiCl 6 Li 6 1

Q. 1 Atomic no. of Mangnesium is 12. And molecular formula of Magnesium Chloride isMgCl2. If the At. no. of aluminium is 13, Write the molecular formula of aluminiumchloride.

Q. 2 Atomic no. of Carbon is 6, and molecular formula of Carbon chloride is CCl4. Atomicno. of boron is 5. Find out and write the molecular formula of boron chloride.Table 1.2 Compounds of Second Period Elements.

Element

Chloride

Oxide

Hydride

Valency

Table No. 1.3 Electronic Configuration of elements of first three Periods.

Mol

ecul

arF

orm

ula

of

Period(Shell) 1K

1

I A/1 II A/2 III A/13 IV A/14 V A/15 VI A/16 VII A/17

2(K,L)

3(K,L,M)

Valency

Element : z symbol(Electronic configuration)

Zero / 18


Important points to remember :Moseley's modern form of the Periodic Law, Periods, Groups, Series, Normal

elements, Inert elements, Transition elements, Inner transition elements, Metalloid, Sub-atomic particles.

Solved Sample QuestionsGive scientific reasons.

1) The last column on the right side of the modern periodic table is called zerogroup/18 or noble gases. (page no. 7)

Expected Answeri) In this group elements have stable electronic configuration with complete

duplet or complete octet.ii) Because of this the valency of this group of element is zero.iii) The atoms of this group of elements form neither ionic nor covalent bond with

other atoms.iv) The elements of the group have their last shell completely filled.

Write the difference between the following.

Periods Groups

···

i) The horizontal rows ofelements in the modernperiodic table are calledperiods.

ii) The period number indicatesthe number of electronicshells present in an atombelonging to that period.

iii) Elements in the same perioddo not show similar Chemicalproperties.

iv) Seven rows are present.

i) The Vertical columns ofelements in the modernperiodic table are calledgroups.

ii) The group number indicatesthe number of electrons inouter shell of an atombelonging to that group.

iii) The elements is the samegroup show similar chemicalproperties.

iv) Eighteen columns arepresent.


Chapter 2Electrolysis

(Marks - 4, Marks with option 7)

Introduction :You must have read in the newspapers about mishaps and accidents caused due

to lightening falling on the earth. Lightening occurs when the clouds collide with eachother. When lightening falls on the earth its electric level is much greater than that of theearth which is zero. This level of electric energy is called potential. Difference betweenelectric level is called potential difference. Difference between electric level causes electriccurrent.1) Conductivity of substance :

Every substance is made up of atoms and molecules. Substances having freeelectrons in large numbers in their atoms conduct electricity.

Electric conductors are three main types. We are going to study electrolyticconductors.2) Comparison between Electrolytes and Non Electrolytes :

Electrolytes Non Electrolytes

3) Difference between anion and cationAnion Cation

i) A substance whose aqueoussolution can conduct electriccurrent is called electrolyte.

ii) Most of the electrolytes areelectrovalent compounds.

iii) All acids, bases and saltsare electrolytes. Molten saltssome covalent compounds(HCl, NH3) undergo ionisationon dissolving in water. Theyare also electrolytes.

i) A substance whose aqueoussolution can not conductelectric current is called non-electrolyte.

ii) Non-electrolytes are co-valent compounds.

iii) Organic compunds likeglucose, urea, cane sugaralcohol are non electrolytes.

i) Anions are negativelycharged ions.

ii) During electrolysis aniongives electrons andbecomes neutral.

iii) During electrolysis anionattracts towards anode,hence the name anion.

i) Cations are positively chargedions.

ii) During electrolysis cationaccepts electrons andbecomes neutral.

iii) During electrolysis cationattracts towards cathode, hencethe name cation.


Note - Positively charged electrode is known as anode and negatively charged electrodeis known as cathode.4) For types of conductors and definitions of electrolyte and non-electrolytes refer to textbook page no. 13,14.5) Electrolysis of Copper Chloride :(Observe Fig 2.2 on 16 from the text-book) Both the electrodes are carbon rods. Open endof Carbon rod attached to positive terminal of the battery is called as anode. Open endof Carbon rod attached to the negative terminal of the battery is called as cathode.The observation and inference of the experiment is as follows :

The chemical reaction during electrolysis of copper chloride solutions :a) Reaction at Cathode :Positively charged copper ions attract towards negative electrode, accept electrons andconvert into copper metal

b) Reaction at anode :Negatively charged chloride ions attract towards positive electrode, give electrons andconvert into chlorine gas.

Note : During electrolysis of copper chloride, chloride ion (Cl–) gives away electrons andcopper ion (Cu2+) accepts the electrons and copper and chlorine form is elemental form.6) Electroplating :

Refer to Fig. no. 2.3 on page 18 of the text book.Note the following points about the process -

a) An article to be electroplated should be used as negative terminal (cathode)b) A rod of the less active metal to be coated on the article is used as positive

terminal (anode)c) The electrolyte used should be of the same metal, which is used as anode.

For example -For electroplating of silver on copper article, Copper article should be treated as

cathode and silver rod should be treated as anode.

Changes Observation Inference

1) At cathode

2) At anode

3) Colour ofelectrolyte

1) Reddish deposit isseen.

2) Bubbles of a gasare observed.

3) Blue colour startsfading.

1) Copper is deposited atCathode.

2) The gas given out ischlorine.

3) Due to decreasingconcentration of copperchloride moleculescolour fades.

Cu2+(aq)

+ 2e– →Cu(s)

2Cl– (aq)

→ Cl2(g)

2e–


The electrolyte should be a solution of silver nitrate.Go through and study Table no. 2.1 for the process.

7) Anodising Technique -Get information about the process (described) on page no. 18,19 of the text book.)

and practical applications.8) Ion as charge Carriers in living system :

Every living being is made up of cells. Cell contains Cell-sap and inorganic ions.They control the functions of cells. (Read more information about the process on page nos.19, 20 of the text book.)Points to remember :

i) Electric potential is the level of electric energy.ii) Electric current flows from higher electric potential to lower electric potential.iii) Electric conductors are of three types

1) Gaseous conductors2) Metallic (Electronic) conductors3) Electrolytic conductors

iv) Electrolytic conductors conduct electric current by movement of ions.

· Electrolytes : These are the substances in the molten state or whose aqueoussolutions conduct electric current.

· Non-Electrolytes : These are the substances which do not conduct electricity eitherin the molten state or in the aqueous state.

· Electrolytes : All acids, bases, salts.

· Non-Electrolytes : Carbon compounds like glucose, sugar, urea, alcohol etc.

· Electrolysis : It is the process of decomposition of an electrolyte by the passage ofelectric current.

· Electroplating and anodising are the applications of electrolysis.

· Electroplating is a process by which a metal or an alloy is coated with another lessactive but more attractive metal, using electrolysis.

· Anodising is another application of electrolysis where the surface of the aluminiumanode is covered by a thin film of aluminium oxide to make the aluminium surfaceresistant to corrosion and abrasion.

· During electrolysis, cations move towards cathode and anions move towards theanode.

· When aqueous copper chloride solution is electrolysed, copper is deposited at thecathode and chlorine is evolved at the anode. Due to ionisation of copper chloride,the no. molecules of copper chloride in the solution decreases and hence the colourfades.

· Many phenomena in living organisms are controlled by ion transport across cellmembrane.


· Healthy heart requires proper K+/Na+ balance in the body.Solved Sample Questions :1) Give scientific reason -

Distilled water is a bad conductor of electricity.Ans : a) Pure distilled water being a covalent compound does not dissociate.

b) As it does not dissociate, we cannot get cations and anions. As there isno movement of ions, distilled water does not carry current. Hence it isa bad conductor of electricity.

···


Chapter 3Strength of Solutions


Introduction :We use large number of solutions in our daily life. e.g. tea, coffee,

sherbat,medicines, essences, preservatives. Solutions play vital role in our life. We aregoing to study solutions, types of solutions from a chemical point of view.3.1 Study the definitions of - solution, solvent, solute, aqueous solution, non-aqueoussolution.Types of solutions according to state of solute and solvent.

Note - Identify solvent, solute from the solutions used in daily life.3.2 Ionisation and Dissociation -a) Ionisation -

Ionic solutions when dissolved in water turns into positive and negative ions. Theprocess is called ionisation.b) Dissociation -

The process of separation of positive ions and negative ions in the solution of ioniccompound.

Solutions is called dissociation.Note that in any solution, ionisation is the first stage and dissosiation in the secondstage.

Acidity of Base

Sr.No.

Base AcidityNo. of OH– ions in

the molecule

1.2.3.4.

Sodium hydroxide (NaOH)Ammonium hydroxide (NH

4OH)

Calcium hydroxide [Ca(OH)2]

Aluminium hydroxide [Al(OH)3]

1123

1123

Sr.No.

Types of Solution ExampleNature of

Solvent Solute

1.2.3.4.5.

Solid in liquidGas in liquidGas in gasLiquid in liquidSolid in solid

liquidliquidgaseousliquidsolid

solidgaseousgaseousliquidsolid

salt solutionsoda waterairwater in milkalloys e.g. brass


Neutralisation :The reaction in which H+ ions from acid and OH– ions from base combine to form

H2O moecule, is known as neutralisation.The reaction between base and acid isNaOH + HCl → NaCl + H

2O

Note : ionic form of NaOH is Na+ OH–

and that of HCl is H+ Cl–

A) Points to remember (page nos. are given in the bracket)i) Solution, aqueous, solution non-aqueous solution (24)ii) Acid, Base (25)iii) Strond acid, weak acid, strong base, weak base (26)

neutralisation reaction (26)iv) Equivalent weight : equi. w.t. of an acid

Equivalent weight of a base, basicity of an acid, (27)acidity of base (28)Normality (28)

3.3 Study Arrhenius theory from the text book (page no. 25 to 28). Also familiarize withthe terms like strong acid (HCl) strong base (NaOH) weak acid (CH3COOH) weak base(NH4OH)

Sr.No

Acid / Base Example Percentage ofdissociation

1

2

3

4

Strong acid

Weak acid

Strong base

Weak base

Hydrochloric acid (HCl)Sulphuric acid (H

2SO

4)

Nitric acid (HNO3)

Acetic acidCytric acidLactic acidSodium hydroxide (NaOH)Potassium hydroxide (KOH)ammonium hydroxidecalcium hydroxide

to a largeextent

to a lesserextent

to a largeextent

to a lesserextent


3.4 Study the concept of equivalent weight (Page no. 27 of the text-book)Go through the table of basicity of an acid and acidity of base.Basicity of Acid :

B) Study the following formulae, Use appropriate formula to solve the numericals :

i) Equi. wt. of acid =

ii) Equi. wt. of base =

iii) Normality (N) =

iv) Molarity (M) =

v) No. of moles of solute (n) =

vi) from (iv) and (v) we get,

Molarity (M) =

M =

vii) Normality Equation :N

1V

1 = N

2V

2

N1 = Normality of an acid / N

2 = Normality of base

V1 = Volume of an acid / V

2 = Volume of base

unit of Normality is N and that of volume is ml.

Sr.No.

Acid BasicityNo. of H+ ions in

the molecule

1.2.3.4.

Hydrochloric acid (HCl)Nitric acid (HNO

3)

Sulphuric acid (H2SO

4)

Phosphoric acid (H3PO

4)

1123

1123

Molecular mass of baseAcidity of base

Wt. of solute in gramGram equivalent wt. × Volume in litre

Wt. of solute in gramMol. mass of solute × Volume in litre

Mass of solute in gramMol. mass of solute

No. of moles of solute (n)Volume of solution in litre (V)

nV

Molecular mass of acidBasicity of acid


1) Relation between molecular mass and equivalent weight of an acid or a base.

Note : u is the unit.2) In normality equation -

N1V1 = N2V2

N1 = Normality of an acid (unit N)V1 = Volume of an acid (unit ml)N

2 = Normality of a base

V2 = Volume of a base

Points to Remember :

· Solution - It is a homogeneous mixture of two or more different substnaces.

· Solution = Solute + SolventSolute is the dissolved substance in the solution and is a minor component while

solvent is the major component of the solution in which the solute is dissolved.

· According to Arrhenius theory, when dissolved in water, an acid releases (H+) ions anda base releases (OH

–) ions.

· Neutralisation - An acid and a base in their aqueous solutions react with each otherto form salt and water

· Basicity of an acid and acidity of a base depends on the number of replaceable H+

and OH– ions present in the acid and base respectively.

· Standard Solution - A solution whose concentration is accurately known.

· Normality = Basicity × Molarity (For acid)

· Normality = Acidity × Molarity (For base)

· Normality equation : N1 × V

1 = N

2 × V

2 .

· Weight dissolved = Normality × Gram equivalent weight per litre of solution.

Acid / Base Molecular Mass Equivalent weight

1) HCl

2) H2SO

4

3) HNO3

4) NaOH

5) KOH

6) Ca(OH)2

36.5 u

98 u

63 u

40 u

56 u

74 u

36.5 u1 = 36.5 u

98 u2 = 49 u

63 u1

= 63 u

40 u1

= 40 u

56 u1

= 56 u

74 u2

= 37 u


1) Solved Sample Questions

2) Give Scientific reasons :Due to excessive use of chemical fertilizers, fiels lose its fertility.

Ans : Land is basic in nature. Land becomes salty due to excessive use of chemicalfertilizers. These basic substances in the soil react with the acids in the fertilizersand produce salts. In excessive salty soil, the plants cannot grow and thereforefields lose its fertility.

3) Solved examples -i) Text book Q. 4 (35) 1st example in the table.HCl - mass of solute in solution = 18.25 g.Volume of the solution = 1000 ml. Find normality.

Normality of HCl =

=

=

= = 0.5 N.

ii) Q. 4 i) An acid is 0.01 N. 9 ml of this acid required 10 ml of basic solution forcomplete neutralisation. Find the normality of base and weight of base dissolved in1000ml of solution.(Equivalent weight of base = 56.)

Acids Bases

1) All acids contain (H+)ions

2) In aqueous solutionacids releasehydrogen ions (H+)

3) Acids are sour totaste

4) Acids turn bule litmusto red.

1) All Bases contain (OH–)

ions2) In aqueous solution

bases release hydroxylions (OH

–)

3) Bases are corrosive, henceshould not be tasted.

4) Bases turn red litmus toblue.

12

18.2536.5

10001000

×

Weight of solute in gramGram equivalent weight × Volume in litre

18.25

36.5


Solution -Given -

Normality of acid N1 = 0.01 NVolume of acid V1 = 9 mlVolume of base V2 = 10 mlNormality of base N2 = ?Weight of base dissolved in 1000ml of solution = ?

Acid Base N1 × V1 = N2 × V2

0.01 × 9 = N2 × 10

ˆ=

N2

ˆ N2

= 0.009 N

ˆ Normality of base = 0.009 N.Weight of base dissolved in 1000 ml means in1 litre of solution = Normality × Equivalent weight

= 0.009 × 56= 0.504 g

···

0.01 × 910


Chapter 4Current Electricity


Introduction :Now-a-days electricity is being used for daily activities of human being. So that

when there is no power supply, life gets disturbed. For domestic use; electrical applianceslike refrigerator, oven, hot plate, mixer etc. are used for daily activities in kitchen. Forwashing clothes; washing machine is used. So the demand for electricity is increasing,while the generation of electricity has not increased in the same rate that of the demand.Knowledge : In the 9th std. text book previous study the structure of atom and the mainconstituents of the atom.A) Some important concepts, terms and definitions (Study carefully)

(In bracket page number is given from text book).1) Static electricity (page 37)2) Current electricity (page 37)3) Conductors of electricity (page 38)4) Insulators (page 38)5) Semiconductors (page 38)6) Simple Voltaic Cell (page 39 fig. 4.2)7) Direction of conventional current in the wire (page 40 fig. 4.4)8) Definitions and units of Coulomb, Volt and Ampere (42)9) Ohm's law (page 44)10) Super conductors (page 48)11) Electromotive force (page 49)12) The equivalent - resistance when connected in series (page 51)13) The equivalent resistance when connected in parallel. (page 52)

B) Draw and lable the diagrams :(Study carefully and practice)1) Atoms of hydrogen and lithium (page 38) (fig. 4.2)2) Simple Voltaic cell (page 39) (fig. 4,2)3) Verification of Ohm's law [(page 46, fig. 4.7 (a)]4) Connection diagram of resistances in series. (page 51, fig. 4.9)5) Connection diagram of resistances in parallel. (page 52, fig. 4.10)

C) Observe the following table and classify domestic objects :Conductors Insulators Semiconductors

Gold, Silver, Copper,Aluminium, Iron, Graphite,aqueous solution of salts,like NaCl

Rubber, Plastic,glass, mica,porcelein, etc.

Germenium,gallium, Silicon


D) Symbols commonly used in circuit diagrams study carefully and practice (page 43,table 4.1)

E) For details of concept of potential and potential difference (refer page 41 and 42)F) Resistance of a conductor and factors on which resistance of a conductor depends

(page 45)G) What are Ohmic conductors and non Ohmic conductors, study V against I graphs for

them. (page 47, 48, fig. 4.8)H) Study the following formulae and make use of these for solving numericals.

1) Potential difference (P.D.) between two points

ˆ V =

Here, V = Potential difference (Volts)W = Work done (Joules)Q = Electric charge (Coulomb)

ˆ 1 Volt =

2) Electric Current (I)

Current =

ˆ I =

Here, I = Electric Current (Ampere)Q = Electric charge (Coulomb)t = time (second)

ˆ 1 Ampere =

3) Ohm's law equation form :

= Constant

Here V = potential difference (Volts)I = electric Current (Ampere)

The constant in the above relation is called resistance of the conductor and isdenoted by R.

Chargetime

Qt

1 Coulomb1 Second

VI

VI

ˆ = R

WQ

Work done (W)Electric charge (Q)

P.D. =

1 Joule1 Coulomb


This is the symbolic form of Ohm's law.

= 1 Ohm

(N. B. :- ' Ω' This symbol is used for ohm.)

4) R = is the relation between electrical resistance (R), length of the conductor(L) and area of cross of the conductor (A). ρ is constant of proportion and is calledresistivity of the material.

R = Electrical resistance (Ohm)L = Length of the conductor (meter)A = Area of cross section of conductor(m2 i.e. square meter)ρ = Resistivity (Ohm-meter)

5) Resistances in series and equivalent resistancesRs = R1 + R2 + R3 + ................. + Rn

Here Rs = Equivalent resistanceR1, R2, R3 .............. Rn are various resistances connected in series combination.

This is a general equation.For three resistances connected in series combination the formula will beRs = R1 + R2 + R3

8) Resistances in parallel and equivalent resistance :

This will be a general form,For three resistances connected in parallel combination use the following formula.

7) Learn the following conversions :i) 1 Newton = 105 dynesii) 1 Volt = 1000 millivolts = 103 millivolt (or mv)iii) 1 Ampere = 1000 milliampere = 103 mA.iv) 1 Meter = 100 cm.v) 1 sq. meter = 100 × 100 sq.cm. = 104 cm2.

1 Volt1 Ampere

ρ LA

1R

p

1R

1

1R

2

1R

3

= + +

1R

p

1R

1

1R

2

1R

3= + + + .............+

1R

n


Learn the following symbols for electrical terms and make use of them.

8) Observe the table for difference between resistances in series and inparallel combition.

Some Illustrative Examples :1) Calculate the potential difference V across a 10Ω resistor carrying a current 0.2A.Ans. : Given Resistance (R) = 10Ω

Electric current (I) = 0.2 A; V = ?

Formula : R = substituing the values,VI

ˆ 10 = ˆ V = 10 × 0.2 ˆ Potential difference (V) = 2 Volts

V0.2

Term Symbol Unit(Mks)

Unitsymbol

1. Electric force2. Electric charge3. Potential

difference4. Electric

current5. Time6. Electrical

resistance

FQV

I

tR

NewtonCoulombVolt

Ampere

SecondOhm

NCV

A

sΩ

Resistances in series Resistances in parallel

i) Many resistances areconnected one afteranother

ii) Equivalent resistancewill be given byR

s = R

1 + R

2 + R

3 +

................. + Rn

iii) Rs is greater than R

1,

R2, ......., R

n.

iv) Series combination isused to increase theresistance of a circuit.

i) A number of resistancesare connected betweentwo common points.

ii) Equivalent resistance Rp

will be given by

iii) Rp is less than R

1, R

2,

......., Rn.

iv) Parallel combination isused to reduce theresistance of a circuit.

1R

p

1R

1

1R

2= + .....+

1R

n


2) Calculate the resistance of the conductor if Potential difference is 1.5 Volt and 300 mAcurrent passes through it.

Ans. : Given P.D. (V) = 1.5 Volt;Current (I) = 300 mA = 0.3 A; R = ?

Formula : R = Substituting the values

R = R = = 5

ˆ Resistance of the conductor = 5 Ω3) You are given two resistances 20 Ω and 5 Ω. What will be their equivalent resistance

(a) in series (b) in parallel combination.Ans. :Given R

1 = 20Ω; R

2 = 5Ω.

(a) In series combination,R

s = R

1 + R

2 R

s = 20 + 5 = 25Ω.

ˆ In series combination equivalent resistance = 25 ohms(b) In parallel Combination,

ˆ = +

ˆ = =

ˆ =

ˆ Rp = 4 Ohm

4) Resistors of 16 ohms and 4 ohms are connected in parallel combination and 5 ohmsresistor is connected in series combination with them. Find the combined resistance,

Ans. : Given : R1 = 16Ω ; R

2 = 4Ω,

these are connected in parallel,

VI

1.50.3

153

1R

p

1R

1

1R

2= +

1R

p

120

15

1R

p

1 + 420

520

1R

p

14

1R

p

ˆ = +

ˆ = +

ˆ =

1R

1

1R

2

1R

p

116

14

1R

p

1 + 416


Now Rp will act as R1 and R

2 will be 5 Ω,

ˆ In series combination,Rs = R1 + R2

ˆ Rs = +

ˆ Rs = 3.2 + 5 = 8.2 Ω.

5) 8 ohm and 4 ohm resistors are connected in parallel combination and the e.m.f. of the

cell is 3 volt and internal resistance ohm.Find the total current in the circuit.

Ans. :Formula : Total voltage generated by the battary is given by the formula :E = IR + Ir = I (R + r) ..........................IE = E.M.F. of the cell = 3 Volt,Internal resistance of the cell (r) = ohm,

First we have to find R = ?In this case R

1 = 8 ohm and R

2 = 4 ohm resistors are connected in parallel

combination,

Now substituting the values of E, R, r in eqn (I) we get,

3 = I ( + )

ˆ 3 = I ( )

ˆ 3 × = I ˆ I = Ampere = 0.75 Aˆ Total current in the circuit = 0.75 A.

1Rp

1R1

1R2

ˆ = +

1R

p

18

14ˆ = +

1R

p

1 + 28ˆ =

83

ˆ Rp = ohm

83

43

123

312

34

43

ˆ =

ˆ Rp = Ω,

1R

p

516

165

165

51

43


6) Three resistance of each 12 ohm are connected 1st in series combination, then inparallel combination. Determine their equivalent resistance in each case.

Ans : Given R1 = 12 ohm, R

2 = 12 ohm.

Also R3 = 12 ohm,First consider in series combination;Rs = R1 + R2 + R3

ˆRs = 12 + 12 + 12 = 36 ohm

Now in parallel combination,

Q. 2 Give scientific reasons :1) Potential difference of source of current (i.e. cell) is less than e.m.f.Ans : As e.m.f. of the source is the work done by the source in raising a unit positive

charge from its lower potential end to higher potential end. The energy imported to thecharge by the source is used to circulate the charge round the circuit againstopposition to external circuit and internal resistance of the source. Therefore e.m.f.(E) is greater than the potential difference (V) between its terminals.

2) The plates of heating devices such as toaster, an electric iron are made of an alloyrather than a pure metal.

Ans. :A good conductor of a given size has a low resistance. Copper is a good conductorwhile some alloys like nichrome and constantan have a high resistance. So the heatwill be produced more, when current is passed through nichrome coil or plates.Themelting point of nichrome is also higher than pure metal. That is why the material oftoaster electric iron are made of an alloy like nichrome rather than pure metal.

Instructions :This lession is important from the point of examination as well as for scoring more

marks. Different types of questions are asked on this lesson.- Learn by heart the definitions and rules.- Practice the diagrams properly.- Solve all types of sums for practiceQuestions like 'Derive the equation' can be asked on this lesson. e.g. Derive an

equation for equivalent resistance for three resistances in series / parallel.

···

1R

p

1R

1

1R

2

ˆ = + +1R

3

1R

p

112

112ˆ = + +

112

1Rp

1 + 1 + 112ˆ = = =

ˆ = ˆ Rp = 4 ohm

ˆ Resistance in series = 36 ohm and resistance in parallel = 4 ohm

312

14

1R

p

14


Chapter 5Effects of Electric Current


Introduction :Today our most of the daily activities depend upon electric power, e.g. mixer,

refrigerator, heater, oven, T.V., radios, even recharging of the cell phone requires electricpower supply. When power supply breaks down, our many activities stop and life getsdisturbed. In this chapter we are going to study the heating effect and magnetic effect ofelectric current and their practical applications.Previous knowledge : In the previous chapter we have studied some important conceptsabout electric current, like resistance of a conductor.A) Some important conceptds, terms and definitions - study carefully them.(Numbers in the bracket shows the page numbers from the text book)1) Heating effect of an electric current (page 60)2) Joule's law (page 63)3) Magnetic effect of an electric current (page 66)4) Right hand rule (page 69)5) Direct current and Alternating current (page 71)B) Draw and label the diagrams and practice1) Verification of Joule's law (fig. 5.1) (page 61)2) Oersted's experiment (fig. 5.3) (page 66)3) Lines of magnetic field due to current carrying straight line conductor (fig. 5.5)

(page 68)4) Electric bell (fig. 5.9) (page 72)5) Telephone ear piece (fig. 5.10) (page 73)C) Study the following formulae carefully and make use of these formulae for solvingnumericals.1) Joule's law formulae :

H = I2Rt JoulesHere, H = Quantity of heat produced

I = Electric current (Ampere)R = Electrical resistance (Ohms)t = time (seconds)

To convert the above heat in calories, substitute1 calorie = 4.18 Joules

By Ohm's law we substitute I =

H = caloriesI2 R t4.18 V

R


we gets,

Again by same process we get,

ˆ Various forms of Joule's formula will be as follows :

i) H = I2Rt Joules ii) H = calories

iii) H = calories iv) H = calories

* (Cal is the short form used for calories.)2) Electric Power

P = VIP = electric power (Watts)V = Electric potential difference (Volts)I = Electric current (Ampere)

By Ohm's law we substitute, V = IRThe above equation will be -

P = Here ,V = Potential difference (Volts)R = Electrical resistance (ohms)

N.B. : 1) 1 Watt =

1 kilowatt = 1000 watts2) If we observe the electric bulb,-We see the following information -

(a) The power of the bulb (in Watts)(b) The potential difference (in Volts)

e.g. 40 Watts, 250 Volts. It means the power of the bulb is 40 Watts, and it worksfully at 250 Volts P.D. Hence we observe dim light when the voltage is lowered.D) Study carefully the following units.

1) The quantity of heat generated in a conductor depends upon the following factors..... (page 63)

2) Application of the heating effect of electric current (page 64, 65)3) Magnetic effect of electric current (page 66, 67)4) Solenoid and magnetic field produced by solenoid (page 70, 71)5) Direct and alternating current information. (page 71)

H = caloriesV2 t4.18 R

H = caloriesV I t4.18

V I t4.18

V2 t4.18 R

I2 Rt4.18

V2

R

1 Joule1 second


6) Safety precautions while using electrical appliances:a) Precautions against bad insulations (page 74)b) Precautions against improper earthing (page 75)c) General precautions for safety. (page 75)

E) Study the following information carefully :1) The resistance of the conductor depends on the material used. Gold, silver,

metals have very low resistance. But these are noble metals, hence for conduction ofelectric current wires of gold, silver are practically impossible. Copper and aluminium arealso good conductors and have low resistance. So for electric wiring purpose copper oraluminium wires are used.

2) The resistance of the conductor also depends upon the area of cross-section.Smaller the area of cross-section, larger will be the resistance. Therefore in electric bulbvery thin hairy wire of tungston metal in the form of coil is used. Due to coil formationlength of the wire increases, which shows that resistance is directly proportional to thelength, i.e. larger the length of wire, larger will be the resistance. So in heater, geyser thenichrome coil is used

3) In a safety fuse lead allloy wire is used. Because lead has very low melting point,hence when, high current flows through the circuit, the fuse wire gets heated and melted.The circuit is broken and current stops flowing, so the electric appliance will not bedamaged. For different types of electric appliances fuses of suitable capacities are used.

4)

(N.B. - w.r.t. mean with respect to)

Solved Sample QuestionsDifference between A.C. and D.C.

Types of metal Uses w.r.t. electricity

1) Copper, aluminium2) Nichrome3) Tungston

Conduction wires, connection wiresHeater, geysers, electric iron, etc.Electric bulb

Direct Current (D.C.) Alternating Current (A.C.)

1. The direct current always flowsin one direction.

2. It is non-oscillating currentgenerated by the source.

3. Generally D.C. is generatedfrom an electric cell/battery.

1. Alternating current reverses itsdirection periodically.

2. It is oscillating currentgenerated by the source.

3. Alternating current isgenerated by A. C. generator.


Illustrative examples :1) Calculate the heat generated in a coil of resistance 209 ohm and 0.5 amp. current ispassed through it for 2 minutes.Ans. : Given Resistance (R) = 209 ohm

Current (I) = 0.5 amp.time (t) = 2 min = 2 × 60 = 120 sec.

Formula H = calorie.

ˆ H = calories

ˆ H = calories

ˆ H = 1500 caloriesˆ The heat generated in the coil = 1500 cals.

2) Calculate the heat generated in an electric iron, if P.D. is applied 240 Volts, and 418-mA current is passed for 1 minute.Ans. : Given P.D. (V) = 240 Volts,

Current (I) = 418 mA = 0.418 Amp.time (t) = 1 min = 60 sec.

Formula H = calorie.

ˆ H = calories

ˆ H = 1440 caloriesˆ Heat generated in the electric iron = 1440 cals.

3) Find the resistance of 40 Watt, 240 Volt bulb.Ans. : Given : Power (P) = 40 Watt

P.D. (V) = 240 VR = ?

Formula P = Substituting the values.

ˆ 40 = ˆ R =

ˆ R = 1440 ohmsˆ The resistance of the bulb = 1440 ohm.

I2 R t4.18

(0.5)2 × 209 × 1204.18

0.5 × 0.5 × 209 × 120 × 100418

VIt4.18

240 × 0.418 × 604.18

VIt4.18

V2

R(240)2

R240 × 240

40


V2 tR

4) Heat generated in a conductor of resistance 40Ω in 1 minute is 150 Joule. Calculatethe P.D. applied across it to produce above heat.Ans. : Given Resistance (R) = 40 Ω

time (t) = 1min = 60 sec.Heat generated (H) = 150 Joule

P.D. (V) = ?

Formula : H = Joules substituting the values.

ˆ 150 =

ˆ 150 × = V2

ˆ = V2

V2 = 100ˆ V = 100ˆ V = 10 volts.P. D. between two points = 10 volts.

Q. 2 Give scientific reasons :1) Filament of incandescent lamp is made of tungston :Ans. :The resistance of tungston is very high, so if current is passed through tungstoncoil, due to its high resistance it becomes white hot which emits light. Also the meltingpoint of tungston is very high. So it will not melt at that temperature. Therefore the filamentof incandescent lamp is made of tungston.2) Fuse is made of material having low melting point.Ans.: The function of the fuse is to protect the electrical appliances from sudden rise ofpotential difference in the circuit. Therefore if such incidence happens, due to low meltingpoint of the fuse it melts and the circuit breaks. Thus protecting the appliances connectedin that circuit. Therefore generally fuse is made of lead alloy because the melting pointof lead is low.

···

V2 × 6040

4060

150 × 4060

√


Chapter 6Energy Sources


Introduction :In modern world, we need energy in every walk of life. Energy in various forms is

used to cook food, for entertainment, for travel. Gas is used in kitchen, petrol or dieselis used in vehicles. These energy sources are depleting very fast; which has resulted inenergy crisis.Previous knowledge -

Students know the basic concepts of energy fuels.The important concepts / laws from the chapter.i) Classification of energy sources.

a) Non-renewable energy sources.b) Renewable energy sources.(for definition of the above refer to the textbook page no. 81)

1) Energy sources and their classification :

2) Solar energy is the most promising energy source; but there are some limitations forthe use of solar energy. The point is discussed in detail on page no. 87,88 of the textbook. Go through the details to understand the point.3) Wind energy, tidal energy, geothermal energy are the sources of energy. But theavailability of these sources depends upon the environmental conditions. Try to collectmore information about the hydroelectric projects in the country. Read about the micro andmini hydroelectric power plants from the text book (page no. 85, 86)4) Observe the figures of solar cooker (fig. 6.9 page 88), solar water heater (fig, no. 6.10page 89). Try to sketch and label the figures.5) Solar Cells

It is one of the main device to convert solar energy directly into electrical energy.Solar cells are extensively used as main source of energy for artificial satellites.6) Read more about nuclear energy and two ways to obtain the energy from the text - book(page no. 90)

Non-renewableenergy cources

Renewableenergy cources

Firewood, cow dung,charcoal, coal,kerosene, cookinggas; petrol, dieseletc.

Wind energy, tidalenergy, geothermalenergy, energy fromflowing water, solarenergy, energy frombiomass.


Difference between Nuclear fission and Nuclear fusion (Breeder reaction)

Note - Nuclear fission and breeder reaction are one and the same. Breeder reaction iscontrolled chain reaction.

There is a slight difference between working of breeder reactor and burner reactor.Go through the text-book page nos. 90 and 91 for the same.6) Bio-diesel :

This is a renewable energy source. Collect more information about the oil producingseed plants, cultivation of the plants, use of waste land to cultivate these plants. Formerits of biodiesel fuel, see text-book page os. 93, 94.7) Calorific value of fuel -

Get information from the text-book page no. 97. Know the merits of gaseous fuel.8) Important figures :

Try to draw and label following diagramsi) Solar cooker (fig. 6.9 page 88)ii) Solar Water heater (fig. 6.10, page 89)iii) Nuclear fission (fig. 6.11 page 91)iv) Biogas plant (fig. 6.12, page 93)

Points to remember -1) Renewable and Non-renewable

energy sources2) Appliances based on the use of solar energy.3) Ways to obtain nuclear energy4) Types of fuels with proper examples5) Calorific value of fuels - definition, unit

Solved sample questionsQ. 1 Give scientific reasons.1) We have to search for new renewable energy sources.Ans. : i) Currently fossil fuels like petrol, diesel, kerosene, natural gas are mainly used

as conventional energy sources.ii) These sources are in great demand and are used in large quantities. But these

sources are limited and getting exhausted at fast rate.

Nuclear fission(Breeder reaction)

Nuclear fusion

1) Radioactive material likeUranium - 235 convertsinto fragments releasinglarge amount of heatenergy

2) Bombardment ofneutrons is essential tocarry out the reaction.

1) Hydrogen atomscombine to form helium,releasing large amountof heat energy.

2) High temperature isrequired to carry out thereaction.


iii) Hence we have to search for new renewable energy sources.2) Wind mills require specific locations.Ans. : i) Location must be at some height and requires rigid support.

ii) must have strong steady wind blowing for most of the year.iii) hence wind mills require specific locations.

Q. 2 Distinguish between.

···

Biomass Bio gasi) Biomass refers to

wood, biological wasteproducts

ii) It burns with smoke

i) Biogas is the mixtureof methane, carbon-dioxide and hydrogen-sulphide.

ii) It burns without smoke


Chapter 7Types of Energy


Introduction :We are familiar with different forms of energy — thermal energy, light energy,

sound energy, magnetic energy. We are going to study mechanical energy in this chapter.7.1 Points to remember –

i) What is energy? (page 101)ii) Types of energy

a) Potential energy (page 102) formula (page 104)b) Kinetic energy (page 105) formula (page 106)

iii) units - CGS, MKS (page106)iv) Law of conservation of energy (page 107)

7.2 Study fig. no. 7.1 on page 103 and read more about the work done while liftingan object through the height 'h' from A to B

Note that, if θ is the angle between a constant force F acting on a body and adisplacement 'r' of the body caused by this force, then the work done by the forceisW = F.r cosθWhen F and r are in the same direction,θ becomes 0 and cos 0 = 1. Hence

Work done = W = Fr.cosθ = F× rUnits of Potential energy and Kinetic energy:

Units of work and energy is same.In CGS system, unit of energy is dyne-cmIt is also called as 'erg'In MKS system, unit of energy is Newton-meterIt is also called as 'Joule'

1 Joule = 107 erg.A) Potential Energy P.E. :

P.E. = mghP.E. = Potential Energyg = gravitational accelerationh = height of the objectIt is clear from the above equation, that P.E. of a particular object will changeaccording to the value of 'h'


When the object is at rest on the earth's surface 'h' becomes zero.When angle between force and displacement is 900. Then work done becomes Obecause,

W = Fr cos θ= Fr cos 90= Fr × 0 (ˆcos 900 = 0)= 0

When an object rolls on the ground h = 0, hence P.E. = 0B) Kinetic Energy [K.E.]

K.E. = mv2

K.E. = Kinetic energym = mass of an objectv = velocity of the object

It is clear from the above equation, that K.E. of a particular object will changeaccording to the value of 'v'.When the object is at rest, its velocity is zero.Hence its K.E. becomes zero.

C) Law of conservation of Energy -E = P.E. + K.E. (E = Total energy)∴ E = mgh + mv2

i) When we throw the object upward or downward, the total energy of the object atany moment is always constant.When we throw the object upward, its K.E. is maximum and P.E. is zeroconversely, if we drop the object from a height, its PE is maximum and KE isminimum.During transit, when one energy increases, the other decreases at the same rate.Hence total energy remains constant.

Note - While throwing the object upwards, K E changes from maximum to zero, at thesame time P.E. changes from zero to maximum.ii) Study the various examples of transformation of energy from the text book. (pagenos. 112, 113, 114).

Solved Sample questionsQ.1 Give scientific reasons

i) The work done on an object by a conservative force is zero. If it has come backto the same point from where it started.

Ans. i) Work done on an object by conservative force depends only on initial and finalpositions and not on path followed.ii) An object comes to the same point where it is started.iii) Hence work done on an object by a conservative force is zero.

12

12


Q. 2 Solve the numericals.1) Energy of 2J is used to lift a block of 0.5 kg. How high will it rise?

(g = 10 m/s2)Ans. : Given E = Energy = 2J

m = mass = 0.5 kgg = 10 m/s2

h = ?E = mghˆ 2 J = 0.5 kg × 10 m/s2 × h

ˆ h = = 0.4 m

(Height attained by the block = 0.4 m)

···

2 J0.5 kg × 10m/s2


Chapter 8Power


Introduction :In our daily life we use strength as power. But these two terms have different

scientific meaning. If the same work is done for different time duration, then we say thepower is different in scientific view. In this chapter we are going to study about power andits units and applicationsPrevious knowledge : In previous standard we might have been studied about work andenergy and their definitions and applications. We also know that the units of work andenergy are same. viz. In CGS unit it is Erg, while in MKS unit it is Joule.A) Some important concepts, definitions and units : (The number in the bracket ispage number from text-book)

1) Power : definition, unit (page 118)2) Unit of work used in the industry. (page 119)

B) Study thoroughly the following information and practice for solving numericals.1) Table No. 1 Work, power, Energy units

2) Other units of power :1 kilowatt (KW) = 1000 Watt1 Horse power (H.P.) = 746 Watt

3) In industry the unit of work, also energy is expressed as kilowatt-hour (K.W. hr.) Forconsumption of electricity it is also KW-hr and is called as unit.

We know that 1 Kilowatt = 1000 Wattsand 1 hour = 3600 seconds.

4) Study carefully the following.1) Work = Force × displacement

ˆ W = F × sUnit of force (F)

In CGS system the unit of force is dyne and in MKS system it is Newton.1 Newton = 105 dyne.

Units of displacement :In CGS system unit of displacement is cm and in MKS system it is meter (m)

Physicalquantity

Symbolused

CGS Unit MKS Unit

WorkPowerEnergyForce

WPEF

Erg.Erg/secondErgDyne

JouleJoule/second i.e. wattJouleNewton


If we lift any object through height 'h' (perpendicular) from ground level, in suchcase we use following formula for work.

W = mghm = massg = gravitational accelerationh = height

2) Power =

taking w = Fs we get

P = We know = V

ˆ P = F × becomes P = F × V

N.B. Study carefully table No. 8.1 from the text book.

Solved SampleQuesions1) A man draws a bucket of water from a well 10 m deep; in 20 seconds. If the mass of

water drawn is 20 kg. Find the power used by the man? (g = 10m/s2)Ans. Given m = 20 kg, g = 10m/s2; s = 10m, t = 20s, P = power =?

Formula = Power (P) =

ˆ P =

ˆ P = 100 WPower used by man = 100 W.

[N.B. - Here for simplicity of calculations g = 10 m/s2 is given]2) Calculate the power of the crane which lifts the load of 600 kg to height of 10m in 2

minutes. (g= 9.8 m/s2)Given : m = 600 kg, g = 9.8 m/s2, h = 10 m

t = 2 minutes = 120 secondsPower = ?

Power = =

=

= 490 Wattpower of crane = 490 WattAlso note that in above formula P = and P = (i.e. h = s)

···

Worktime ˆ P =

Wt

Fst

st

st

mgst

20 kg × 10 m/s2 × 1020 s

Wt

mght

600 kg × 9.8 m/s2 × 10 m120 seconds

mght

mgst


Chapter 9Sound


9.0 Previous knowledge :Sound is produced by a vibrating body. Vibrating tuning fork produces sound.

Vibrating string, vibrating plates also produce sound. Harmonium and trumpet vibrate airand produce sound. These instruments are sources of sound.9.1 Production of sound :

Sound travels in the form of longitudinal waves consisting of alternate compressionand rarefaction. Due to vibrations of an object when adjacent layers of air are pressed,compression is formed. When adjacent layers get seperated, rarefactions are formed.[Observe fig 9.2 in the text book). When these longitudinal waves in the air reach the ear,the ear drum is set into vibrations. These vibrations are communicated to brain and weget sensation of hearing.9.2 Medium is essential for propogation of soundPrevious knowledge : solid, liquid and gas are the mediaPoints to study : i) Sound waves do not travel through vaccum. They need a medium forpropogation. Refer to experiment on pg. 128 i.e. Sound waves need a medium.ii) The velocity of sound in air at 00C is 332 m/s. Velocity of sound is different in differentmedia.Refer table no. (9.1) in the text book i.e. Velocity of sound in different media.9.3 Propogation of sound in different mediaPrevious Knowledge : The number of cycles or vibrations completed in one second istermed as the frequency of the vibrations.The MKS unit of frequency is Hertz. (i.e. Hz)Points to study :

i) The sound which has frequency between 20 Hz to 20,000 Hz is audible sound.This frequency range is audible range for human beings.

ii) The sound having frequency below 20 Hz and above 20,000 Hz cannot be heardby human being.

iii) To understand how sound is propogated in air, refer experiment on page no. 129in the text book.

iv) Study of table no. (9.1) on page no. 130, we can understand that the velocityof sound is maximum in the solids, less in the liquids and least in the gases.Velocity of light is greater than velocity of sound that is why we see flash oflighting from the clouds before the thunder is heard although both occursimultaneously.


9.4 Reflection of sound waves :Previous Knowledge :

i) Some hill-stations have echo points, which attract the tourists.ii) When you shout into a well or inside an empty hall, you hear your own sound

after some time.i.e. reflection of sound.

Points to study : Echo effect means the reflection of same sound periodically. Sound isincident on plane surface and it gets reflected. This sound is called as reflectedsound. Echo can be heard only if the reflected sound reaches the ear at 1/10th ofa second after the direct sound is heard.Velocity of sound in air at ordinary temperatures is 340 m/s.The minimum distance covered within 1/10th second will be

340 × = 34 m

In other words echo is heard only if the reflecting surface is at least at a distanceof 17 meters

9.5 Effect of wind, Temperature and Humidity on velocity of sound :Previous knowledge : Loudspeakers are used for announcements in the village fair and

advertisements.Points to study :

i) Wind - When sound travels in the direction of the wind, the velocity of sound isgreater. When sound travels in a direction opposite to that of the wind. The velocityof sound lowers.ii) Temparature : Velocity of sound depends upon temperature. Increase in thetemperature increases the velocity of sound in air.iii) Humidity : Humidity depends upon the water vapour present in air. The velocityof the sound in moist air is greater than the velocity of the sound in dry air.Increases in humidity increases the velocity of sound in air.

9.6 Intensity of sound :Intensity is the amount of sound energy received per second from the source ofsound.Unit of intensity of sound is decibel (dB). For sound intensity of different sources,refer to table (9.2) on page no. 136 in the text book.

9.7 Sound pollution or noise : Noise is sound dumped into the atmosphere.1) Children making noise in the classroom2) Noise of fire crakers in Diwali.Unwanted sound is called noise. This unwanted sound makes sound pollution.

Causes of noise :Noise is caused by various sources.1) Internal sources.2) External sources.Noise pollution is a health hazard.

110


Refer to page 137 and 138 of textbook for effect of noise pollution and measuresof noise control.

Solved Sample QuestionsQ. 1 What is Echo?Ans. :Reflected sound is known as echoQ. 2 How the principle of echo is used to measure the depth of sea?Ans : The principle of echo is used in the (SONAR) system of ship to detect the depth

of the sea. From the transmitter in the ship sharp pulses of sound are emitted.These pulses travel downword and get reflected from the sea bed. The reflectedsound is detected by the receiver in the ship.

The time interval between the production of sound and its reflection is recorded.Knowing the velocity of sound in water and time, the depth of sea can be determinedby following formula

Depth of sea = Velocity of sound in water ×

Q. 3 Whistle of a passing train is clearly heard on a quiet misty night.Ans : At night when humidity tends to rise, the sound travels faster. Hence sound can be

heard more clearly on a quiet misty night.Hence whistle of a passing train is clearly heard on a quiet misty night (pg. no. 136)

Q. 4 Define - Intensity of soundAns Intensity is the amount of sound energy received per second from the source of

sound.Q. 5 What is sound pollution?Ans. An unnecessary, unpleasant, intolerable or unwanted sound is called noise or sound

pollutionIllustrative Examples :Solve the following examples :1) A person hears a thunder 6 seconds after a flash of lightning is seen, at what

distance the lightning is struck neglecting speed of light?(Speed of sound in air is 340m/s)Solution - Speed of sound = 340m/sTime = 6sDistance = ?Distance = speed of sound × time

= 340 × 6= 2040 m

(The lightning has struck at a distance 2040 m from the observer.)2) A person observes a smoke from the cannon. After 3 seconds he hears the bang.

The cannon is 1020 m away from the observer. Calculate the velocity of sound in air?Ans Solution

Distance = 1020 mtime = 3 s

time2


Speed of sound = ?Distance = speed of sound × time

1020 = speed of sound × 3

ˆ Speed of sound =

= 340 m/s(Speed of sound = 340 m/s)

···

10203


Chapter 10Heat


Previous knowledge :Heat is one of the forms of energy and it can be obtained by transforming any

other form of the energy.Sun, wood, charcoal, cooking gas are some of the sources of heat.Heat can be produced by chemical reactions, flow of electric current and nuclear

reactions.10.1 Anomalous behaviour of water :Previous knowledge : Any substance when heated expands and contracts on cooling.

Most of the liquids expand on heating and contract on cooling. But water showsa remarkable exceptional behaviour between OC0 to 40C

When water is heated from 00C initially it contracts in volume upto 40C instead ofexpansion.

The behaviour of the water between 00C to 40C is called anomalous expansion ofwater.

The anomalous behaviour of water can be demonstrated with the help of Hope'sapparatus.Practice the diagram of Hope's Apparatus. Refer pg no. 144 in the text book

At 40C, the volume of water is minimum. Hence density of water is maximum at40C. Density of ice is less than water, therefore ice floats on water. If we take water ina glass and put some pieces of ice in it, we observe that ice floats on water.Following are some examples of anomalous expansion of water.

i) In cold countries; fishes, acquatic animals and plants remain alive.ii) In cold countries sometimes water enters into the crevices of rocks. When

temperature falls below 40C water expands and tremendous pressure is exertedon rocks. So these rocks crumble into pieces.iii) In winter, the pipe lines carrying water burst when the temperature of atmosphere

falls below 40C10.2 Humidity and dewpoint :i) The presence of the water vapour in the atmosphere plays an important role in

everyday life. The amount of the water vapour present in the atmosphere determinesthe nature of the weather.

Before raining we perspire a lot. Then we say that humidity in air is increasedand soon it will rain.

Similarly the region nearby sea such as Bombay, Goa, Ratnagiri etc. percentageof humidity is more in these region. So we perspire more.


ii) In winter, we observe dewdrops on grass and on vehicles. If we keep pieces of ice instainless steel glass then we observe dewdrops on the outer surface of the glass.Because the water vapour which is in air gets condensed on the outer surface ofthe glass. Study the definitions of absolute humidity, relative humidity and dew pointfrom text book (pg. no. 147, 148)

10.3 Units of Heat :Study the definitions of calorie, kilo calorie, specific heat capacity from text book(pg. no. 149, 150)

10.4 Specific heat capacity :This property changes from material to material (Refer to the experiment on pg. no.149 in the text book)Specific heat capacity of water is highest (Study table no. 10.1 on pg no. 150. StudyMKS and CGS unit of sp. heat capacity.

10.5 Principle of heat exchange :We know that for daily bathing we mix cold water to hot water. Here hot waterprovides heat to cold water and cold water absorbs heat from the hot water.When hot body and cold body is kept together the temperature of hot body goeson decreasing while that of the cold body goes on increasing until both the bodiesattain the same common temperature within a short while.

Formula : Heat lost by the hot body = Heat gained by the cold body.Using this formula solve the numerical examples.

Solved Sample QuestionsExample :1) Certain mass of water at 640C is mixed with an equal mass of water at 220C. What

will be the resulting temperature of the mixture?Ans. Given, Let mass of water = m gm

Specific heat of water = 1 cal/g0Ct1 = 640C, t

2 = 220C t

3 =? (temp. of mixture)

Formula : Heat lost by hot body = Heat gained by cold bodymc (t

1 – t

3) = mc (t

3 – t

2)

ˆ t1

– t3 = t

3 – t

2

ˆ 64 – t

3 = t

3 – 22

ˆ m is same for hot and cold water

ˆ 2 t3 = (64 + 22)0C

ˆ t3 =( )0C

ˆ t3 = 430C

Ans. The temperature of the mixture will be 430C.

862


* Specific heat of water is 1It is the highest than other most known liquids and solids.

* Due to high specific heat, hot water is used in the hot water bags and used forheating purposes.

···


Chapter 11Light


Introduction :Light is a form of energy. Light is necessary to see the objects. We can hardly

see anything in dark. Light is electromagnetic waves.A) Points to remember (text book page nos of the relevant topic in bracket) -1) Visible light (158)2) Refraction of light (159)3) Refraction of light through a glass slab (161)4) Refractive index (163)5) Laws of refraction (165)6) Critical angle, total internal reflection (166)7) Types of lenses (167)8) Some terms used in connection with lenses.

Centre of curvature, radii of curvature, optical axis, principal foci (167, 168)9) Lens formula (176)10) Focal length (f) of convex lens is positive and of concave lens is negative

(fig. 11.13 (a) (b) page 175)11) Cartesian sign conventions (174, 175)12) Magnification and diopter (176, 177)13) Passage of light through a prism (179,180)14) Deviation and angle of minium deviation (181)15) Defects of eye (185, 186, 187)16) Persistence of vision (193)B) Draw and practice the ray diagrams

i) Refraction of light through a glass slab(fig. 11.4, page 161)

ii) Path of light through a prism (fig. 11.16, page 181)iii) A simple microscope (fig. 11.25 page 190)iv) A compound microscope (fig. 11.26, page 191)v) An astronimical telescope (fig. 11.27, page 193)

C) Note that to construct an image of a given object placed in front of a lens by usingany two of the three specialised rays. Read carefully instructions on page no 170of the text-book.

D) Go through the tables carefully -Table no. 11.2 and 11.3

E) Draw and practice the ray diagramfig. 11.10(b) (page 173)


Note : The image of an object placed anywhere in front of concave lens is always virtualerect and diminished.

G) Differenciate

Convex lens Concave lens

1) Convex lens is also calledas converging lens

2)

3) Convex lens is thicker atthe centre than at theedges.

4) Focal length is positive5) If any object is placed at

F1 and beyond the image

is real and inverted. If it isplaced between F

1 and O,

the image is virtual anderect.

1) Concave lens is also calledas diverging lens

2)

3) Concave lens is thinner atthe centre than at theedges.

4) Focal length is negative.5) Image is always virtual

erect, diminished.

1) Consists of a convex lens

2) An object is placed withinthe focal length of convexlens

3) We get magnified image

4) It is used by watch makers,jewellers and while readingsmall font words.

1) Consists of two convexlenses.(Objective and eye piece)

2) An object is placed justbeyond the focal length ofthe objective lens.

3) We get highly magnifiedimage.

4) It is used to observe plantcell, animal cells, bacteriaetc.

A simple microscope A compound microscope


Short sightedness

1) Defect is due to slightelongation of the eye ballor bulging of the eye lens.

2) A person suffereing fromthis defect can see nearbyobjects clearly but unableto see objects at longdistances.

3) The image of the distantobject is in front of retina.

4) It can be corrected byusing concave lens ofsuitable focal length.

1) Defect is due to slightflattening of the eye ball inthe horizontal direction.

2) A person suffering from thisdefect can see distantobjects clearly but unableto see nearby objects.

3) The image of the nearbyobject is formed behind theretina.

4) It can be corrected byusing convex lens ofsuitable focal length.

Long sightedness

Remember the formulae :

i) Reflactive index of glass = =

∠ i = angle of incidence, ∠ r = angle of refraction

ii) Refractive index of water in a tank =

iii) Lens formula :

– =

v = image distanceu = object distancef = focal length

iv) Magnification (m) :

m = =

m = magnificationq = height of the imagep = height of the object

Real depthApparent depth

sin isin r

Real depthApparent depth

1v

1u

1f

qp

vu


v) Power of a lens

P =

P = Power of the lens in dioptersf = focal length in meters

vi) If two lenses of focal lengths f1 and f2 are kept in contact with each other, theircombined focal length is given by,

= + , P1 = , P2 =

P = P1 + P2 P = Power

Note : Go through the topics 'Persistence of vision' and 'Perception of colour'(page nos. 193, 194, 195)

Solved Sample QuestionsQ. 1 Give scientific reason

1) Rapid movement of burning incense stick appears as a complete circle of redlight.

Ans. Principle : The impression of image formed on retina lasts for 1/16 of a second evernafter the object is removed. This effect is called Persistence of vision.

(1 mark)Explanation : While the successive positions of the burning tip are being seen byyou, the images of the previous positions are still there on the retina and you getthe illusion of the complete circle of red light.

(1 mark)Solve the numerical.

An image of a object placed in front of a convex lens at a distance 20 cm is formedat a distance of 60 cm from the lens. The image is real.Then find :

1) focal length of the lens2) size of object is 6 cms, find the size of the image

i) u = – 20 cm v = 60 cm (Image is real) Find f = ?

By using

– = mark

ˆ – =

ˆ + =

1f

1f

1f1

1f2

1f1

1f2

1v

1u

1f

12

160

1(– 20)

1f

160

1 20

1f


ˆ =

ˆ =

ˆ f = = 15 cm

ˆ The focal length of lens is 15 cms. 1/2 markii) size of object (P) = 6 cm

size of image (q) = .........?

ˆ = 1/2 mark

ˆ =

ˆ q = = – 18 cm

– sign shows the image is inverted image.ˆ Size of the image is 18 cms.

4) What is power of accomodation ? 2 marksAns We see objects when its image is formed on retina. In normal human eye retina to

lens distance does not change. So for different object distance (u) the focal length(f) is adjusted such that the image distance (v) remains constant. This ability of theeye lens of adjusting the focal length is known as Power of accomodation. Forobserving distant objects the lens becomes thin and while observing nearer objectsit becomes slightly bulging. This is brought about by the ciliary muscles.

···

1 + 360

1f

460

1f

604

qP

vu

q6

60– 20

60 × 6– 20


Chapter 12Modern Physics


Introduction :In modern technological world, research in every walk of life is going on.Cancer can be cured by using radiotherapy. X-rays are gift of science to the

human being. Bones can be screened with the help of x-rays. If a child swallows a coin,x-rays can pinpoint the location of the coin and surgeon can take out the coin withminimum effort. By exposing the vegetables and other food stuffs to radiation byradioisotopes, their life can be increased. Research in modern physics helps the mankindin material comforts.A) Important points / concepts

i) Radioactivity - definition (page 200)ii) Concept of nuclear fission (page 207)iii) chain reaction (page 208)iv) concept of nuclear fusion (page 210)v) Law of radioactivity (page 211)vi) half life period (page 211)vii) Carbon dating (page 213)

B) Read carefully following table

C) Study table 12.1 on page 203 and answer the following questions:i) Nature and charge of α, β particles and gamma raysii) Compare – α, β particles (4 points)iii) Compare – α, β particles gamma rays (4 points)iv) Compare ,, β particals, gamma rays (4 points)v) Name the particles, rays having highest and lowest penetrating power.vi) Effect of radioactive transformation on radioactive elements.

D) Draw and lable the diagrams :i) Production of α, β, γ radiations (fig. 12.1 page 201)ii) Production of cathode rays (fig. 12.2 page 204)

Sr.No.

Name of the scientist discovery

1

2

3

4

Bequerel

Pierre and Madam Curie

W.C. Rontgen

Otto Hahn and Strassman

Radioactivity of uranium salt

Discovery of radious, polonium

Discovery of x-ray

Nuclear fission of U - 235


iii) Production of X-rays (fig. 12.3 page 206)iv) Chain reaction (fig. 12.4 page 209)

E) Study properties and uses of the following :i) Cathode rays (page 204)ii) X rays (page 206, 207)iii) Radio isotopes (page 212)

F) Write the equation of reaction, when U is bombarded with thermal neutrons(page 208)

G) Write the equation of reaction taking place in the sun. (page 210)H) What is the use of carbon dating ? (page 213)I) Study the illustrative examples (page 214, 215)

Solved Sample QuestionsQ. 1 Give scientific reason (2 marks each)

1) γ - radiations are not deflected by electric field.γ - radiations are neutral means they have no charge, hence they are notdeflected by electric field.

2) X-rays are invisibleX-rays are electromagnetic waves having very short wavelength(almost 5 × 10–8m)Therefore they are invisible.

Q. 2 Write short noteUses of Cathode rays1) Cathode rays produce fluorescence in many substances. This property is usedin Cathode ray oscilloscope (CRO) and computer monitor.2) C.R.O. is used to measure A.C. and D.C. Voltage frequency, phase etc.3) The picture tube of television is a Cathode ray tube in which a beam of Cathoderays incident on the screen, and produces a picture on the screen.4) Cathode rays are used to produce X rays

Q. 3 Solve the following numerical (2 mark)Uraniumm of mass number 238 and atomic number 92 emits 5 α particles and 2β particles and gets converted into polonium. Find the mass number and atomicnumber of polonium.

Ans Emission of 1 α particle from the atom its mass number reduces by 4 and atomicnumber reduces by 2.1) ˆ By emission of 5 α particles, the mass number is reduced by 5 × 4 = 20 and

atomic number is reduced by 5 × 2 = 10.2) Emission of 1β particle from the atom its mass number remains the same and

atomic number increases by 1ˆ by emmision of 2β particles atomic number increases by 2ˆ Total loss in mass number is 20 and total loss in atomic number is 10 and

23592


increase in atomic number is 2.ˆ mass number of polonium = 238 – 20 = 218Atomic number of polonium = 92 – 10 + 2 = 84

. ˆ mass number of polonium is 218 and atomic number is 84

···

238

92U

–5α–2β

218

84Po


Part II - Self Study Material

Chapter 1 : Metals and non - metals

(Mark - 5, Marks with option - 8)

Metals and non - metals and metalloids are the three types of elements. Most of

the metals are in solid state (except mercury). Almost all metals have lustre. They

have high density. They are good conductors of heat and electricity. They are

malleable and ductile. The properties of non - metals are exactly opposite. There

is a marked difference in their chemical properties. Most metals react with dilute

acids to form hydrogen (H2) gas. Oxides of metals are basic in nature whereas

oxides of non - metals are acidic. Oxides of a few metals are amphoteric in

nature.

Important concepts and principles are as follows : (Page no. of textbook given in

brackets)

1. Difference between metals and nonmetals (Pg. no. 1)

2. Minerals (definition) (Pg. no. 4)

3. Ores (definition) (Pg. no. 4)

4. Steps involved in extraction of metal (Pg. no. 5)

a) preliminary treatment

b) chemical reduction

c) refining

5. Ores of iron and Aluminium (Pg. no. 4)

6. Reduction of Iron oxides by Blast Furnace (Pg. no. 7)

7. Reactions in the Blast Furnace (Pg. no. 8)

8. Extraction and Reduction of Aluminium (Pg. no. 9)

9. Electrolytic Reaction of Alumina (Pg. no. 10)

10. Alloys (definition) (Pg. no. 10)

Properties and commercial use (Pg. no. 11)

Table 1.3

11. Sulphur - Occurence, Allotropes flower of sulphur (Pg. no. 12, 13)

12. Uses of sulphur (Pg. no. 14)

13. Gases :


a) H2S - Preparation, Properties, Uses (Pg. no. 15, 16, 17)

b) CO2 - Preparation, Properties, Uses (Pg. no. 18, 19)

c) Ammonia (NH3) Preparation, Properties, Uses (Pg. no. 20, 21, 22)

Points to remember : Minerals are non - renewable natural resources.

Physical and chemical properties of metals and non - metals are different.

Metallurgy is the science and technology of metals.

Usually metals exist in their ores in combined state.

There are three main steps in the extraction of a metal from its ore :-

a) Preliminary treatment

b) Chemical reduction

c) refining

Principal ores of iron are : haemetite, limonite, magnetite and siderite.

Blast furnace is used for extraction of iron.

Bayer’s Process is used for extraction of aluminium.

A homogenous mixture of two or more metals or a metal and non - metal is

called alloy.

Rhombic sulphur and monoclinic sulphur are the main allotropes of crystalline

sulphur.

Sublimate of sulphur is called ‘flower of sulphur’.

N. B. : Study of metals and non - metals, it means their physical properties, such

as state, colour, melting point, boiling point, density, etc; chemical properties and

their uses in industry as well as domestic.


Solved sample questions

Ques. 1 Rewrite the statements by selecting the correct option :(each ½ mark)

(1) The metal existing in liquid state at room temperature is .

(Pg. 1)

a) mercury b) copper c) bromine d) chlorine

Ans. The metal existing in liquid state at room temperature is mercury.

Ques. 2 State whether the following statements are true or false : iffalse, write the correct statement. (each ½ mark)

(1) Iodine is a lustrous metal. (Pg. 1)

Ans. False

Correct statement : Iodine is a lustrous non - metal.

Ques. 3 Rewrite Column II and Column III so as to match Column I(each ½ mark)

(Pg.22)

(Pg. 8)

(Pg.16)

(Pg.14)

Column I Column II Column III

1

2

3

4

Ammonium chloride

Calcium silicate

Hydrogen sulphide

Sulphur

Heavier than air

fungicide

CaSio3

White fumes

slag

vulcanisation ofrubberdry cell

reducing agent

a

b

c

d

i

ii

iii

iv

Column I Column II Column III

1

2

3

4

Ammonium chloride

Calcium silicate

Hydrogen sulphide

Sulphur

White fumes

CaSiO3

heavier than air

fungicide

dry cell

slag

reducing agent

vulcanisation ofrubber

a

b

c

d

i

ii

iii

iv

Ans.


Ques. 4 Give scientific reasons : (each 2 marks)(1) Metals have electropositive character. (Pg. 2)

Ans. In the electronic configuration of atoms, metals have less than four

electrons in the outermost orbit. The atoms of metals form ions by

losing their valence electrons. As a result, the positive charge

increases and so atoms form positive ions. Hence metals have

electropositive character.

Ques. 5 Distinguish between : (each 2 marks) (Pg. 1)(1) Metals and Non metals

Ques. 6 Write balanced equations for the following : (each 2 marks)(1) Zinc powder is treated with dilute sulphuric acid.

Ans. When zinc powder is treated with dilute sulphuric acid, zinc sulphate

is formed and hydrogen gas is evolved.

Zn + 2H2SO4 ZnSO4 + H2 ↑ (Pg. 3)

Ques. 7 Write the chemical formula : (each ½ mark)(i) Sodium bicarbonate

Ans. Sodium bicarbonate - NaHCO3 (Pg. 19)

Ans.Metals Non Metals

(i) Metals are solid at

ordinary temperature

(except mercury)

(ii) Metals have lustre.

(iii) Metals are good conductors

of heat and electricity.

(iv) Metals are malleable and

ductile.

(i) Non metals are solid, liquid

and gaseous at ordinary

temperature.

(ii) Non metals do not have

lustre.

(iii) Non metals are poor

conductors of heat and

electricity. (except graphite)

(iv) Non metals are not malleable

or ductile.


Ques. 8 (Define) or write the definition : (each 1 mark)(i) Reduction (Pg. 5)

Ans. The chemical reaction in which oxygen is separated from a compound

in the oxide form is called reduction.

Ques. 9 Write any two chemical properties of ammonia ( 2 marks)(pg.21)Ans. (i) Ammonia is neither combustible nor a supporter of combustion.

(ii) Ammonia reacts at high temperature with oxygen and oxidises to nitric

oxide.

Ques. 10 Write any two uses of sulphur (2 marks)Ans. (i) Sulphur is used in fireworks. (Pg. 14)

(ii) Sulphur is used as an antiseptic in ointments.

Ques. 11 Which two substances are used in the laboratory for thepreparation of ammonia gas? What is their proportion? What is

the method of collection of the gas? Write the reason. ( 4 marks)Ans. In the labnoratory, ammonium chloride and slaked lime is taken in a

ratio of 3 : 2 for the preparation of ammonia gas.

Ammonia gas is collected by the downward displacement of air.

Because ammonia is lighter than air. (Pg. 20)


2 : Compounds of Metals and non - metals

(Mark - 5, Marks with option - 8)Introduction -

Most of the compounds which are very useful to us in our day to day life are

the products of chemistry. In this chapter we will study some compounds.

2.1 Sodium bicarbonate; (NaHCO3) : Baking soda

Properties, uses (Pg. 28)

2.2 Sodium carbonate : Na2CO3, 10H2O (washing soda)


The process in which salts lose their water of crystallisation on

exposure to air is called ‘efflorescence’ (Pg. 29)

2.3 Calcium carbonate : CaCO3 (limestone)

Properties, uses (Pg. 29, 30)

2.4 Ferrous sulphate : FeSO4, 7H2O (Green Vitriol)


2.5 Copper sulphate (Blue Vitriol) CuSO4, 5H2O


2.6 Potassium Aluminium Sulphate (Alum) :

[K2SO4 Al2(SO4)3, 24H2O]


Potash alum when heated strongly swells and loses all molecules

of water of crystallization and anhydrous alum is formed.

Anhydrous alum is called ‘burnt alum. (Pg. 32)

2.7 Plaster of Paris : (CaSO4)2 H2O (POP)

Properties, uses (Pg. 32,33)

2.8 Chloride of lime CaOCl2 (Bleaching powder)


Summary : Comparative table of properties and (Pg. 35,36)

uses of compounds


Solved Sample QuestionsQ.1 Rewrite the statements by selecting the correct options :

(each ½ mark)i) Sodium Carbonate is known as ....................... .

Ans. Sodium carbonate is known as washing soda. (Pg. 28)

Q.2 Rewrite the second column to match the first column(each ½ mark)Column I Column IIi) Sodium carbonate a) Baking sodaii) Calcium carbonate b) Washing sodaiii) Sodium bicarbonate c) Blue Vitrioliv) Copper sulphate d) Limestone

Ans. i) Sodium carbonate a) Washing soda (Pg 28)ii) Calcium carbonate b) Limestone (Pg 29)iii) Sodium bicarbonate c) Baking soda (Pg 28)iv) Copper sulphate d) Blue Vitriol (Pg 30)

Q.3 Identify the odd one out of the group (½ mark each)1) Na

2CO

3, CaCO

3, FeSO

4, CuSO

4

Ans. CaCO3 Insoluble in water (Pg 28, 29, 30, 36)

Q.4 State whether the following statements are true or false.Rewrite the correct statement if the given statement is false.(½ mark each)i) Baking soda is used for softening hard water to soft water.

Ans. FalseCorrect statement : Washing soda is used for softening hard waterto soft water. (Pg 28, 29)

Q.5 Give scientific reasons (each 2 marks)i) Baking powder is used in the preparation of cakes

and breads. (Pg 28)


Ans. On heating baking powder, CO2 gas is evolved. Due to CO2 gas.

cakes and bread become light and spongy. Therefore baking powder is used in

the preparation of cakes and breads.

Q.6 Distinguish between the following pairs (2 marks each)1. Baking soda and washing soda

Ans. Baking Soda Washing Soda(Pg 28, 29)i) Amorphous powder i) Crystalline substance

ii) On heating it decomposes ii) on heating it gives out

to give out CO2 gas water of crystallization, and

soda ash is formed.

iii) It is used to make cakes and iii) It is used as a cleansing

bread light and spongy. agent in washing clothes.

Q.7 Write balanced equations of the following reactions(2 marks each)i) Sodium bicarbonate is heated (Pg 28)

Ans. 2NaHCO3 Na2CO3 + H2O + CO2 1 mark

On heating it decomposes to form sodium carbonate, water and

carbon-di-oxide. 1 mark

Q.8 Write any two properties of lime stone (1 mark)Ans. i) It is a white amorphous powder which is insoluble in water.

ii) On heating strongly it decomposes into lime and CO2. (Pg 29)

Q.9 Give two uses of Blue Vitriol (1 mark each)Ans. i) It is used in preparing Bordeaux mixture which is a pesticide, a

mixture of copper sulphate and lime.

ii) It is used in electroplating and electro-refining of metal.

Q.10 What is soda ash ? (2 marks)Ans. On heating washing soda, it loses water of crystallization to form

Heat


white amorphous substance called anhydrous substance. Anhydrous

sodium carbonate which does not contain any water of crystallization is

called soda ash. (Pg 29)

Q.11 What is burnt alum? How is it prepared? (4 marks)Ans. Burnt alum : potash alum when heated strongly swells and loses all

molecules of water of crystallization and anhydrous alum is formed.

2 marks (Pg 32)

K2SO

4 Al

2 (SO

4)3

24H2O K

2SO

4 Al

2 (SO

4)3

+ 24H2O ↑

Crystalline alum Burnt alum

Anhydrous alum is called burnt alum.

Molecular formula - K2SO4 Al2 (SO4)3 1 mark

Burnt alum is used as an ingredient in medicines. 1 mark

Heat

Strongly


3 : Chemistry of Carbon Compounds(Marks - 3, Marks with option - 5)

Introduction -We use many organic compounds in our day to day life. Organic compounds

mostly contain the elements carbon and hydrogen. These compounds are

obtained from animals and plants. They can also be synthesized in the laboratory.

The study of these compounds is called ‘organic chemistry’. In this lesson, we

are going to study the carbon - carbon bond formed in carbon compounds, their

types, the large number of compounds formed and their commercial uses.

3.1 Catenation - Definition, straight chain, branched chain and (Pg 39)

ring compounds

3.2 Hydrocarbon - Definition, chain compounds types (Pg 40)

3.3 Open chain Hydrocarbon - (CnH2n+2) Saturated and (Pg 39, 40)

(CnH2n) Unsaturated hydrocarbon and their examples

3.4 Aromatic hydrocarbon, cyclic hydrocarbon, homologus series (Pg 41)

3.5 Petroleum and its constituents - rock oil, (Pg 41,42)

mineral oil, fossil fuel

Petrochemicals - definition (Pg 42)

Green house effect - Green house gases (Pg 42)

Global warming (Pg 42)

3.6 Commercial importance of some organic compounds (Pg 43)

Methane, Methyl alcohol, Ethylene

Polymerisation - Definition, chemical reaction (Pg 43)

Freon, Acetaldehyde, Acetic acid (Pg 43,44)

Points to remember : Carbon has four valence electrons. Each carbon atom links with other

elements and forms infinite number of compounds.

Two or more carbon atoms link with each other to form straight chain,

branched chain or ring compounds.

The types of bonds formed between two carbon atoms are C - C (single

bond), C = C (double bond) or C ≡ C (triple bond). Many examples of such

compounds are used commercially.

Green house effect - it leads to global warming.


Solved Sample QuestionsQ.1 Rewrite the statements by selecting the correct options :

(each ½ mark)i) The valency of carbon element is ....................... .

(a) 2 (b) 4 (c) 6 (d) 8

Ans. 4 (Pg 39)

ii) ..................... is used as a preservative.

(a) pickle (b) sauce (c) vinegar (d) alcohol

Ans. vinegar (Pg 44)

Q.2 Distinguish between : (2 marks)

Q.3 Give scientific reasons : (2 marks)1. Carbon forms a large anumber of compounds. (Pg 38)

Ans. (i) The atomic number of carbon is 6. Two electrons are present in

K shell and four electrons are present in L shell.

(ii) Carbon can share its four valence electrons with other elements

like H, O, N, Cl, Br, etc.

(iii) Carbon has the property of catenation. Hence carbon can link

with other carbon atoms to form single, double or triple covalent

bonds.

(Pg 39, 40)

Saturated Hydrocarbon

1. All four valencies of each

carbon atom are satisfied

by single bonds.

2. All bonds in this compound

are single bonds.

3. They show less chemical

activity.

4. General formula is

[ Cn H2n + 2 ]

Unsaturated Hydrocarbon

1. Valencies of two carbon

atoms are not satisfied by

single bonds.

2. The bonds are double or

triple.

3. They show greater chemi-

cal activity.

4. General formula is CnH2n-2

or [ Cn H2n ]


4 : Food and Food Adulteration

(Marks - 4, Marks with option - 7)Introduction -

All living organisms require food for their growth and maintenance. Food is

the basic necessity of the body. All the energy required for carrying out the

physiological processes of the body is obtained from food. All the elements (such

as carbon, nitrogen, phosphorus, sulphur, hydrogen, oxygen, etc.) required for the

body are obtained from food. Hence, to get all the nutrients and energy required

for our daily activities, our daily diet must contain the nutrients in the proper

proportion.

4.1 Food - Concept and principles (Pg 47)

Calorie, Food calorie, Food as source of elements (Pg 47)

Food and energy (Pg 48)

4.2 Definition of food, food from plants and animals (Pg 48, 49)

Food groups and their functions - Table 4.1 (Pg 50)

Food pyramid, proportion of nutrients in our daily diet (Pg 52)

4.3 Balanced diet - definition (Pg 51)

Energy required for different groups of people. Table 4.2 (Pg 51)

4.4 Food preparation - Safety measures to be taken to ensure (Pg 52,53)

food safety and cleanliness during food preparation

4.5 Food adulteration - definition (Pg 53)

Milk as complete food, sources of milk and (Pg 53, 54)

proportion of nutrients, Table 4.3

Other important food stuffs, their proportion and uses, (Pg 54, 55)

food adulterants table (Pg 59)

4.6 Standardisation of food - Prevention of Food (Pg 55)

Adulteration Act, Indian Standardisation Institution (ISI) and

Agricultural Marketing (AGMARK)

4.7 Harmful effects of food adulteration and diseases caused (Pg 56)

4.8 Chemical tests for Identification of adulterated food stuffs (Pg 57)


Solved Sample QuestionsQ.1 Answer the following briefly : (4 points, 2 marks)

i) What are the harmful effects of not maintaining food hygiene?

Ans. The harmful effects of not maintaining food hygiene are as follows :

a) Through food; germs, poisonous substances, smoke, dust and

other harmful substances may enter the body.

b) Contamination of food takes place due to the germs.

c) Consumption of such contaminated food is dangerous to health.

d) Consumption of contaminated food leads to food poisoning, (pg53)

vomitting, diarrhoea and stomach pains.


5 : Nutrients


Food plays an important role for growth and to maintain good health. Food is

necessary to stay warm, to carry out our daily activities and to build up tissues.

Food supplies all the necessary chemical nutrients to carry out these functions.

5.1 Nutrients - definition (Pg. 62)

Classification of nutrients (Pg. 62)

5.2 Carbohydrates - sources, functions (Pg. 62, 63)

5.3 Protein - classification, sources and functions (Pg. 63, 64)

5.4 Fats - chemical structure, classification (Pg. 65)

Sources and functions

5.5 Vitamins - Definition, types (Pg. 66, 67, 68, 69)

Sources and functions

5.6 Minerals - Necessity, sources (Pg. 69)

functions, mineral nutrients Table 5.1

5.7 Water - importance, functions and necessity (Pg. 69)

Points to remember : The important components of human food are carbohydrates, proteins, fats,

vitamins, minerals and water.

65 - 80% of the required energy is obtained from carbohydrates.

Proteins are important for the building up of the cells and tissues.

Enzymes produced in the various organs of the body are proteins. Proteins

carry out a variety of functions in the body.

Fats as hormones carry out important functions.

Vitamins are important support for the life. Vitamins are necessary for the

growth, maintenance and good health of the body.

Minerals and water are also important for good health.


Solved Sample QuestionsQ.1 Complete the following table (5 marks)

Q.2 Distinguish between :

Q.3 Give scientific reasons (4 points, 2 marks each)(i) Carbohydrates are known as protein sparing nutrients.

Ans. (a) Proteins are major constituents of our cells and tissues. They are

necessary for the maintenance and growth. Proteins are enzymes

and hormones, hence important.

Column I

i) Vitamin A

ii) Vitamin C

iii) Vitamin E

iv) Vitamin K

v) Disaccharide

sugar

Column II

Retinol

Ascorbic acid

Tocopherol

Phylloquinone

Lactose

Column III

Vision

Collagen

Antioxidant

Blood Clotting

Milk sugar

(Pg. 66)

(Pg. 68)

(Pg. 67)

(Pg. 67)

(Pg. 62)

(Pg. 66)

Water Soluble Vitamins

1. Chemically unstable

2. Nutritional value decreases

when exposed to heat, light

and air.

3. Excess vitamins cannot be

stored in the body.

4. Excess vitamins are excreted

through urine.

5. Consumption of excess

vitamins is not harmful.

6. Should be consumed daily.

7. Vitamins B amd C

Fat Soluble Vitamins

1. Chemically stable

2. Nutritional value is stable as

they are fat based.

3. Excess vitamins are stored

in fatty tissues.

4. Excess vitamins are not

excreted.

5. Consumption of excess

vitamins is harmful.

6. Not necessary to be

consumed daily.

7. Vitamins A, D, E and K


(b) If carbohydrates and fats are not consumed sufficiently, then

proteins are oxidised to provide energy.

(c) At such times, there may be a shortage of proteins in carrying

out important body functions.

(d) If carbohydrates are taken in sufficient amounts then due to the

energy obtained from their oxidation, proteins are spared to carry

out other important functions. Hence, carbohydrates are called as

protein sparing nutrients. (pg.63)


6 : Food Spoilage and Wastage


Food is the basic need of life. Food is of either plant or animal origin. In daily

life different food items are included in diet.

Wheat, rice (cereals) and some legumes are preserved for longtime. Milk is

preserved for few hours. Vegetables, fruits and cooked food spoil in a day. Each

food item has different preservation period.

Various factors causing spoilage of food - some of these factors are within

the food itself and are called intrinsic factors while some are external factors or

extrinsic factors.

6.1 Definition i) food spoilage (Pg. 76)

ii) undesirable changes (Pg. 76)

6.2 Factors causing food spoilage (Pg. 77)

Intrinsic, extrinsic factors; Examples. (Pg. 77)

Factors affecting growth of micro - organisms,

chemical changes (Pg. 78,77)

6.3 Principles of food preservation (Pg. 79)

Explanation, preventing self - decomposition of food, (Pg. 79, 80)

methods of food preservation

6.4 Food wastage : storage and handling (Pg. 81)

6.5 Ways of Quantitative wastage of food (Pg. 81)

a) Defective post - harvest practices

b) Defective methods of storage and distribution

c) Traditional customs (Pg. 81, 82, 83)

6.6 Control of quantitative loss of food (Pg. 83)

proper distribution system, storage (Pg. 83)

6.7 Qualitative loss of nutritive value and different methods. (Pg. 84)

The dropouts of food pipe line (Pg. 83)


Solved Sample QuestionsQ.1 Fill in the blanks (1 mark)

i) .......... is the most accepted method of preserving the milk. (Pg. 80)

ii) Degradation of ..... materials, fruits become soft. (Pg. 78)

iii) Sprouting of onions, potatoes can be stopped by .... radiations.(Pg. 80)

Ans. i) pasteurisation ii) pectic iii) Gamma

Q.2 Rewrite the Columns II and III so as to match Column I (2 marks)

Ans. a) - iii - 2 b) - iv - 1 c) - ii - 3 d) - i - 4

Q.3 State whether the following statements are true or false. Rewritethe correct statement if the given statement is false by changingthe underlined words / phrase.i) Temperature in the range of 50C - 190C is most suitable for

growth

of the micro - organisms. (Pg. 87)

Ans. False

200C to 500C is most suitable for growth of the micro - organisms.

ii) Use of baking soda destroys vit. B complex. (Pg. 87)

Column I

Food

a) milk

b) eggs

c) fruits

d) onions &

potatoes

Column II

Treatment

i) irradiation

ii)preparation

of jam

iii) pasteurization

iv) preparation of

powder

Column III

Principle

1) Drying

2) heat kills micro

organisms

3) sugar in high

concentration

inhibit the

growth of micro

organisms

4) prevents

sprouting

(Pg. 86)


True

Q.4 Give scientific reasons (2 marks)1) Dried food grains remain unspoiled for long periods.

Ans. i) Micro organisms require a lot of water for their growth. The

growth of micro organism is prevented in dry foods due to

absence of water. (Pg. 78)

ii) Natural food contain active enzymes. Enzymes decompose

food in presence of water. Water is absent in dry food so dried

food grains remain unspoiled.

2) Buttermilk should not be kept in brass & copper container.

Ans. i) Lactic acid is present in buttermilk. (Pg. 77)

ii) Acid reacts with metal container leading to undesirable changes.


7 : Diseases and DIsorders - I


The factors affecting human health are disease, illness and sickness. When

human health is affected by external factors, it is known as disease. These

diseases disturb the body physiologically or psychologically. When the internal

structure of the cells is changed, it is known as disorder. Diseases and disorders

definitely affect human health. This chapter provides the necessary and important

information about these diseases and disorders, their preventive measures,

treatment and how to maintain good health.

7.1 Disease - definition (Pg. 88)

7.2 Causes of diseases (Pg. 88)

Triad model of environment (Pg. 89)

Causative agent and host

Causative factors of diseases (Pg. 89, 90, 91, 92)

Table 7.1

7.3 Origin of diseases - cellular causes (Pg. 92, 93)

microbial causes, air borne diseases, water borne diseases

7.4 Molecular causes - Anaemia

Sickle shaped RBC - Fig. 7.1 (Pg. 94)

Genetic causes, environmental causes (Pg. 94, 95)

Chromosomal disorders, Down Syndrome (Pg. 95)

Monogenic disorders - albinism (Pg. 96)

Multifactorial disorders (Pg. 96)

7.5 Environmental diseases - (Pg. 96, 97)

Vehicle borne diseases

7.6 Effects of Tobacco (Pg. 97)

Effects of smoking (Pg. 97)

Effects of Toabcco chewing (Pg. 97)


Solved Sample QuestionsQ.1 Give scientific reasons

i) The consumption of tobacco causes many diseases / disorders.

(2 marks) (Pg. 97)

Ans. i) Tobacco contains nicotine, a poisonous substance.

ii) Tobacco smoke contains compounds like pyridine, ammonia,

aldehyde, furfurol, carbon monoxide, sulphur dioxide which are

cancer causing chemicals.

iii) These carcinogens act on cells leading to uncontrolled cell

division.

iv) In whichever organs, carbon particles stick to the inner sides, it

leads to cancer in the organs.

Q.2 How does coccidioidomycosis spread ? (2 marks) (Pg. 93)Ans. i) This disease spreads through air borne transmission of fungal

spores.

ii) The spores may be present in the dust of hospital wards and

living rooms.

iii) Thus the disease is carried by infected dust.


8 : Diseases and Disorders - II


In the last chapter we have studied origin and causes of diseases. Which

were dangerous to human health. In this chapter we shall study some commonly

occurring diseases that seriously affect social and individual health.

8.1 Cancer - Properties and Causative agents (Pg. 100)

Radiant energy, chemical agents (Pg. 100)

Viruses, other miscellaneous factors (Pg. 101)

8.2 Leprosy - Causes, forms, types (Pg. 101, 102)

stages of the signs of leprosy (Pg. 102)

Preventive and control measures (Pg. 102)

8.3 Malaria - Cause plasmodium vivax (Pg. 102)

infection of parasite due to female

anopheles mosquitos carrying plasmodium (Pg. 103)

Three successive stages, preventive measures (Pg. 103)

8.4 Ascariasis - caused by contaminated

water and foodstuff (Pg. 103)

Spread, treatment, prevention (Pg.103, 104)

and control measures

8.5 Hepatitis - Types, causes (Pg. 104)

Hepatitis A - Communicable disease (Pg. 104)

Preventive measures

Hepatitis B - Preventive measures (Pg. 105)

8.6 Aids - set of chronic disorders

seriousness form, (Pg. 105)

Retrovirus - RNA, DNA, Copy of DNA (Pgs. 104, 105)

Signs - Major and minor (Pg. 106, 107)

Modes of transmission, preventive (Pg. 107)

and control measures

8.7 Awareness about sexual (Pg. 108)

behaviour - health education


Points to remember :Table

Disease Causative Symptoms Mode of Transmission

organism

* Cancer is caused due to uncontrolled cell division

* Awareness about radiant energy, chemicals, virus, smoking,

consumption of tobacco, alcohol consumption, wearing tight clothes

are the factors about which awareness is essential.

***


Solved QuestionsQ.1 Give scientific reasons (2 Marks)

Water should not be allowed to collect around the house. (Pg. 103)

i) Mosquito lays eggs in the water collected around the house.

ii) Malaria is caused by female mosquito

iii) Malarial parasite lives in the RBCs.

iv) Infection of this parasite to human beings occurs by the bite of

the female anopheles mosquito carrying plasmodium.

In order to prevent mosquito from breeding, water should not be

allowed to collect around the house.


9 : Dietary Deficiency Disease


If any nutrient required in the diet is lacking, the individual suffers from a

disease. In this lesson, we are going to see which disease is caused due to the

deficiency of which nutrient.

Balanced diet : The diet which includes all the required nutrients in appro-

priate proportions is known as a balanced diet. (Pg. 112)

Approximate nutritive value of the balanced diet. (Pg. 112)9.1 Protein Energy Malnutrition (PEM) - definition (Pg. 112)

Kwashiorkor and Marasmus are the most serious forms of

PEM according to ICMR

A) Kwashiorkor - characteristics (Pg. 113)

caused due to deficiency in quality (Pg. 113)

and quantity of proteins.

B) Marasmus - characterized by severe wasting (Pg. 114)

Difference between kwashiorkor

and Marasmus - Table 9.1 (Pg. 114)

C) Treatment of PEM - Table 9.2 (Pg. 114)

D) Preventive Measures : 1) Health

Promotion 2) Specific Protection (Pg. 115)

3) Early Diagnosis and Treatment

E) Protein Deficiency in Adults (Pgs. 115, 116)

9.2 Deficiency of Minerals - 24 mineral

elements : Ca, P, Fe, Na K, Mg, I (Pg. 116)

Zn, Cl, F and others.

Trace Elements : Fe, I, F, Zn, Cu, Co, Mo, (Pg. 117)

Deficiency of calcium, Phosphorus

Sodium and Magnesium (Pg. 116)

Iron, Deficiency : Causes, signs and Symptoms, (Pg. 117)

Treatment and Prevention

Iodine deficiency - disorders, prevention (Pg. 118)


Fluorine deficiency - disorders, prevention (Pg. 118)

Deficiency of zinc, copper, molybdenum (Pg. 118)

9.3 Deficiency of vitamins - diseases, (Pgs. 118, 119, 120)

Preventive measures

9.4 Malnutrition : Four forms (Pg. 121)

Factors of Insufficiency of Nutrients (Pg. 121)

(I) Host factors (II) Agent Factors (Pg. 121, 122)

(III) Environmental Factors (Pg. 122, 123)

9.5 Enrichment of food

various Programmes (Pg. 123, 124)

9.6 Beverages - Three groups (Pg. 124)

9.7 Fast foods - Explanation and examples. Vitamin (Pg. 126)

deficiency diseases - Table

Solved QuestionGive scientific reason (2 Marks)

Excess intake of Vitamins B and C does not cause any disease(Pg. )

i) Vitamins B and C are water soluble vitamins.

ii) If excess of vitamins B and C is consumed, they are thrown out of the

body through urine or sweat.

iii) Hence excess intake of Vitamins B and C does not couse any

disease.


10 : Diseases due to Overintake of Some Nutrients


In this Chapter we are going to study the effects of overintake of saturated

fats vitamins, salts and minerals causing various diseases.

10.1 Excessive intake of calories (Pg. 130)

Obesity, Body Mass Index (Pg. 130)

Broca index (Pg. 131)

increased morbidity, increased mortality (Pg. 131)

The preventive and control measures (Pg. 131)

10.2 Excessive intake of saturated fats (Pg. 132)

Arteriosclerosis Hypertension (Pg. 132, 133)

Coronary Heart disease - Prevention

10.3 Excessive intake of fluorine

Dental Fluorosis, skeletal fluorosis (Pg. 134)

10.4 Excessive intake of vitamins, (Pg. 134)

Hypervitaminosis of vitamin A and D (Pg. 135)

10.5 Disadvantages of excessive intake of nutrients

10.6 Controlling measures of excessive intake of nutrients (Pg. 135)

Solved QuestionGive scientific reason (2 Marks)

Regular exercise is essential.

i) Excessive consumption of carbohydrates, proteins and fats in our diet

may cause many diseases.

ii) Digestion and assimilation of these nutrients is necessary.

iii) Failing to do so will lead to obesity.

iv) Hence regular exercise is essential.


11 : Human Health and Hygiene

(Marks -2, Marks with option - 4)Introduction -

Hygienic habits cannot be learnt from books, but they must be developed and

practised in daily routine. The value of health is not fully understood until it is lost.

11.1 Concept of health. (Pg. 140)

Health is fundamental human right

Changing concepts (Pg. 140)

Biomedical, Ecological, Psychosocial, Holistic concepts, (Pg. 140)

Old and new concepts of health fig. 11.1 (Pg. 141)

11.2 Definitions of health (Pg. 141)

11.3 Necessity and General measures (Pg. 142)

Health for all HSR (Pg. 142, 143)

11.4 Personal Hygiene (Pg. 143)

Hygiea, community Hygiene

Personal Hygienic Habits (Pg. 143, 144)

11.5 Community Hygiene

Health care for the people, Health care by the people (Pg. 145)

11.6 Preventive measures

Pollution Definition, control of environmental pollution for

good health. (Pg. 145, 146)

11.7 Prophylaxis against infectious diseases (Pg. 146)

11.8 Proper Education Definition (Pg. 147)

Main objectives : (a) informing people (b) motivating people (Pg. 147)

(c)Guiding into action.

11.9 Population control definition (Pg. 148)

Population education

a) Direct measures (sterilization, operation)

b) Indirect or Educational Measures (Pg. 148)


Solved QuestionsQ.1 Give scientific reasons

1) Tight fitting clothing should be avoided (Pg.145)

Ans. All tight fitting clothing should be avoided as they interfere with normal

circulation of blood, respiration, digestion and the action of muscles.

Q.2 Write short Note1) Environmental Pollution hazards (Pg. 146)

Ans. Environmental pollution causes many health hazards as given

below :

i) The air pollutants like oxides of sulphur cause headache,

conjunctivitis, Pneumonia, coma etc.

ii) Nitrogen oxide causes lung diseases.

iii) The hydrocarbons are carcinogenic.

iv) Metals like Pb, Cd, Hg etc. cause anaemia, damage to RBCs

liver and kidney infection, fatigue anxiety, hypertension, cancer

etc.

Q.3 Give the various primary health care measures. (Pg. 142)Ans. : 1) According to the declaration of Alma Ata conference the

primary health care measures are

i) Education about existing health problem and methods of

preventing and controlling them.

ii) Promotion of food supply and proper nutrition.

iii) An adequate supply of safe drinking water and basic sanitation.

iv) Maternal and child health care including family planning.

v) Immunization against infectious diseases.

vi) Prevention and control of endemic diseases/

vii) Appropriate treatment of common disease and injuries.

viii) Provision of essential drugs.


12 : Biotechnology


Modern age is the age of information and technology. Biotechnology is an

important branch of modern science; develops rapidly for the welfare of human

being. This chapter deals with impact of biotechnology on agriculture, health and

environment.

Previous knowledgeIn std IX DNA is discussed. In the discussion it is stated that DNA molecule

decides hereditary characterization of living beings.

Study the important concepts/terms.

(Text book page no. of relevant matter is given in the bracket)

1) Experiment carried out by scientist Frederick Griffith of ‘Transforming

Principle;. (Page nos. 151, 152)

2) Diagrammatic representation of DNA and gene (Page 153)

3) Biotechnology in agriculture (Page 153, 154)

4) Biotechnology and health (Page 154)

5) Protein products and their uses. (Table 12.1, Page 154)

6) How vaccination is useful to enhance the resistance (Page 154, 155)

7) Explanation : why transgenic protatoes cannot be cooked ? (Page 155)

8) Detailed information about ‘interferon’. (Page 155)

9) How biotechnology is useful to maintain ecological balance ? (Page 156)

10) Information bioremediation. (Page 156)


Solved Sample QuestionsFill in the blanks the correction option from the bracket.1) The experiment of Transforming Principle was carried out by

scientist .........

2) In DNA, nitrogen molecule contains four bases named .........

3) Herbicide ......... is used to kill the herbs.

4) Indian Agriculture Research Institute has developed ......... variety of

mustard.

5) Protein product ......... is used for treating viral infections.

(Pusa Sona, interferon, ACGT, WXY, Glyphosphate, Frederick

Griffith, Pseudomonas)

[(i) Frederick Griffith (ii) ACGT (iii) Glyphospate (iv) Pusa Sona

(v) Interferon]

Q. 2 Give reasons.1) Transgenic potatoes cannot be cooked. (Pg. 155)

Transgenic potatoes cannot be cooked, because cooking would

destroy the ‘protein’ of the disease causing bacteria.

Q. 3 Write Note on (Pg. 156)Biotechnology to maintain ecological balance.

Many of the environmental problems can be solved using modern

biotechnology. In fact traditional procedure of waste - water treatment

and solid waste treatment through waste decomposition are very good

examples of microbial biotechnology.


Solved Sample QuestionsWrite scientific reasons (Each 2 Marks)1) Protein injection is better than vaccination. Expected Answer.

Ans. i) In order to enhance the resistance to a particular disease a

method called vaccination is used.

ii) In this process a disease causing virus bacteria are either

killed or weakened.

iii) These microbes are injected in the body.

iv) In case of typhoid and cholera vaccine, killed bacteria are

used. However in some cases these vaccines can cause the

disease and harm the individual.

v) Now it is possible to change the genetic characteristics of

bacteria so that these bacteria would produce viral or bacterial

proteins in large quantities.

vi) Hence protein injection is better than vaccination.

Write shorts notes1) Haemophilia (Factor VIII)

Expected Answer

i) It is a hereditary disease. This disease carries hereditary

characters from one generation to the next generation.

ii) It is not curable because it is developed from the change in the

genes. (They are caused due to faulty genes)

iii) In haemophilia disease, there is defect in the gene which controls the

function-blood clotting.

Therefore, there is no process of blood clotting. After that, if one gets

injured who is transformed from haemophilia disease then blood

does not clot, it remains bleeding.

iv) Factor VIII is useful for the treatment of haemophilia, which is a

product of biotechnology.


Write short answers.1) What are the functions of gene ?

Expected Answer

Ans. i) A particular part under the DNA chain is called as gene.

ii) It stores the genetic information.

iii) It determines the hereditary characters of human being.


Types of QuestionsI Objective type questions :

1) Rewrite the following statements by selecting the correct option.

2) Rewrite the second column so as to match the first Column

3) Rewrite the columns II and III so as to match column I

4) Consider the relation between column I and II and fill in the column IV to matchthe column III

6) Form pairs from the group of words / phrases having same relationship.

7) Fill in the blanks with proper term from the bracket at the end of the statement

8) Fill in the blanks by choosing the correct option from bracket

9) State whether the following statements are true or false

10) State whether the following statements are true or false. Rewrite the correctstatement if the given statement is false.

11) State whether the following statements are true or false. If the statement isfalse correct the statement by changing the underlined phrase.

12) Fill in the blanks

13) Identify the odd one out

14) Identify the odd one out with reason

15) According to given property identify the odd one out.


II. Short answer type questions

21) Give scientific reasons.22) Distinguish between.23) Distinguish between : Give any two points24) Distinguish between : With respect to two given points.25) Solve the numericals.26) Write balanced equations for the following27) Describe with diagram - formation of ion/molecule28) Write short answers29) Write short notes.30) Write definitions of31) Write laws32) Write properties / characteristics/ symptoms of33) Write uses of34) Write formulae of35) Write units of36) Give examples of37) Give peculiar characteristics of38) Give names of39) Draw and label the diagram40) Short answer type questions.

III) Long answer type questions.51) Explain in detail.52) Write notes on53) Describe process/ procedure/ technique.54) Describe the apparatus with following points

i) principle ii) diagram iii) construction iv) working v)uses.55) Describe the experiment with following points -

i) title ii) apparatus iii) diagram iv) procedurev) observation vi) inference


SCIENCE AND TECHNOLOGY- PART I / IINATURE OF QUESTION-PAPER

Time -2 Hours Max. marks 40

N.B. i) All questions are compulsary.ii) All questions carry equal marks.iii) Draw labelled diagram wherever necessary

Q.1. A) Rewrite the statements by selecting the correct option (4 statements) (02)

B) Match the Pairs (4 pairs) (02)

C) Complete the table/select the option/right or wrong (4 statments) (02)

D) Fill in the blanks/odd one out (4 statements) (02)

Q.2. A) Give scientific reasons (2 out of 4) (04)

B) Differenciate/properties/uses/ examples/ characteristics/ laws/ symptoms/ working etc. (2 out of 4) (04)

Q. 3 A) Solve the numericals/Give balanced equation of (2 out of 4) (04)

B) Long answer type question (1 out of 2) (04)

Q.4. A) Draw and label the diagrams ( 2 out of 4) (04)

B) Long answer type question (1 out of 2) (04)

Q. 5. A) Short answer type questions ( 4 out of 6) (04)

B) Long answer type question ( 1 out of 2) (04)


MAHARASHTRA STATE BOARD OF SECODARYAND HIGHER SECONDARY EDUCATION,


SUB : SCIENCE AND TECHNOLOGY : PART ONE

NAME OF THE CENTRE :

NAME OF THE CANDIDATE :

REGISTRATION NO. :

ADDRESS :

DATE OF BOOKLET RECIEVED :

DATE OF SUBMISSION :N.B.: Write the answer of each question in the space provided. If neces-sary, attach separate sheets for answer. Q. Marks Q. Marks Q. Marks Q. Marks No. No. No. No. 1 11 21 31

2 12 22 32

3 13 23 33

4 14 24 34

5 15 25 35

6 16 26 36

7 17 27 37

8 18 28 38

9 19 29 39

10 20 30 40


Q. Marks Q. Marks Q. Marks Q. Marks No. No. No. No. 41 55 69 83

42 56 70 84

43 57 71 85

44 58 72 86

45 59 73 87

46 60 74 88

47 61 75 89

48 62 76 90

49 63 77

50 64 78

51 65 79

52 66 80

53 67 81

54 68 82


Science and Technology - Part IExercise Section

Chapterwise Serial numbers of questions.

Sr.No.

123456789101112

Name of the chapter Question nos.from - to

Classification of ElementsElectrolysisStrength of solutionsCurrent ElectricityEffects of Electric CurrentEnergy SourcesTypes of EnergyPowerSoundHeatLightModern Physics

01 to 0910 to 1617 to 2223 to 3536 to 4546 to 5152 to 5859 to 6162 to 6768 to 7273 to 8283 to 90


Exercise Section1. Classification of elements

Q. 1) Rewrite the following statement by selecting the correct optioni) ................. is more reactive than sodium

a) Lithium b) potassium c) Hydrogen d) Magnesium.ii) The valance shell of halogen contain ................. electrons.

a) 1 b) 0 c) 7 d) 8iii) On the basis of electronic configuration of elements the periodic table is

divided into ................. blocks.a) 16 b) 7 c) 4 d) 18

iv) The elements of s-bolck and f-block together (except zero group) are called the................. elements.a) Inert b) transition c) Inner transition d) normal

Q. 2) Rewrite the second column so as to match the first columnColumn I Column II

i) Group - 1 a) rare gasesii) Group - 2 b) family of halogeniii) Group - 17 c) family of alkaline earth metalsiv) Group - 18 d) Family of alkali metalsv) zig-zag line e) family of metalloids

Q. 3) Complete the following table

Element Symbol Period Electronic Type of elements

i) Fluorine 9F .............. 2, 7 ..............ii) Neon .............. 3 .............. Neutral element/rare gasesiii) .............. 29Cu 6 .............. Transition elementiv) Cerium 58Ce .............. 2,8,18,18,8,4 .............. Silicon .............. 3 2,8,4 ..............

Q. 4) Find the odd one out (1 mark each)i) carbon, sodium, Nitrogen, Neon → ..............ii) Redon, Chloirne, zenon, Argon → ..............iii) Fluorine, Bromine, Iodine, Silicon → ..............iv) Boron, Carbon, Sulphur, Polonium → ..............v) Sodium, Magnesium, Potassium, Francium → ..............


Q. 5) Give reasons.i) Valency of element of 2nd group is two. (Page no. 7)

ii) All the elements in group B are called transition elements (Page no 10)

iii) Most non-metals have four or more electrons in their outermost shell(page no. 10)

iv) Sodium is more reactive than Lithium, while potassium is more reactive thansodium. (Page no. 7)

v) The valency of halogen is one. (page no. 7)

Q. 6) Write the difference between the following.i) Mendeleev's Periodic table and Modern Periodic table (132)


ii) Group VII A (group 17) and zero group (group 18) (page 7 & 8)

iii) Group I A and group II A (Page 6 & 4)

iv) d-block elements and f-block elements (page no. 8)

v) s-block elements and p-block elements (page no.8)


Q. 7) Give two names of eachi) Alkaline earth metals (page no.7)

ii) Metalliods (page no. 8 & 9)

iii) Subatomic particle with charge -e (page no. 9)

iv) normal elements (page no. 8)

v) Alkali metals (page no. 6)

Q. 8) Classify the elements on the basis of electronic configuration(page no. 8)


Q. 9) Describe four blocks of the periodic table based on the electronic configurationof elements (page 8)

···


2. Electrolysis

Q. 10) Rewrite the following statement by selecting the correct optioni) When an electric current passes through copper chloride solution .................

gas is collected at anode. (page no. 17)a) Oxygen b) hydrogen c) Chlorine d) Carbon dioxide

ii) Electrolytic conductors conduct electricity by movement of .................(page no. 13)a) ions b) electrons c) protons d) atoms

iii) Proper functioning of living cell requires ................. ................. .................inside the cell (page 20)a) high concentration of K+ and high concentration of Na+

b) high concentration of K+ and low concentration of Na+

c) low concentration of K+ and low concentration of Na+

d) low concentration of K+ and high concentration of Na+

Q. 11) Find the odd one out (give reason)i) Benzene. Alcohol, Kerosene, liquid sodium chloride (page 15)

ii) sugar, urea, sodium hydroxide, glycerine

iii) Nitric acid, hydrochloric acid, acetic acid, sulphuric acid (page 15)

Q. 12) State whether the following statements are true or false. If the statementis false, correct it and rewrite it.i) Most of the non-electrolytes are electrovalent compounds. (page 15)

ii) Anode is that electrode at which electrons enter the electrolyte. (page 15)

iii) In anodising technique carbonic acid is used as an electrolyte.


Q. 13) Write two points of difference each of the following.i) Electoplating and Anodising (page 18,19)

ii) Anode and Cathode (page 15)

iii) Electrolytes and non electrolytes (page 15)

Q. 14) Give scientific reasons.i) Aqueous solution of sugar is non-electrolyte. (page 15)

ii) Aqueous solution of HCl can conduct electric current but its solution in benzenecannot. (page 15)


iii) During electroplating, the anode has to be replaced periodically. (page 18)

Q. 15) Explain in brief "Anodising technique".

Q. 16) Draw the labelled diagrams.i) Electrolysis of copper chloride (page 16)


ii) Electric conduction of electrolytes (page 14)

···


3. Strength of Solutions

Q. 17) Fill in the blanks with proper terms from the bracket.i) Basicity of acid depends upon ................. (page no. 27)ii) In neutralisation reaction, volumes of acid and base are always .................

proportional to their normality. (page 30)iii) Brass is the example ................. type.

(directly, inversely, no. of H+ ions, no. of H– ions, solid + solid, solid + liquid)Q. 18) Rewrite the second column so as to match the first coloumn.

Column I Column IIi) Monobasic acid a) NaOHii) Diabasic acid b) HCliii) Tribasic acid c) H

2SO

4

d) H3PO

4

Q. 19) Write the names only -i) Aqueous solutions of hydroxides of first group metals .............. (page 28)

ii) The solution whose concentration is accurately known ..............(page 28)

iii) The acids which dissociate to a lesser extent and give less number hydrogenions in solution ..............(page 26)

Q. 20) Give reasons.i) Potassium hydroxide is a strong base (page 26)


ii) Equivalent weight and molecular mass of nitric acid is same. (page 27)

iii) Brass is an alloy. (page 25)

Q. 21) Explain neutralisation reaction. (page 26)

Q. 22) Solve the following.i) NaOH solution is 0.2 N, 10 ml of 0.05 M H

2SO

4 is required for complete

neutralisation. Find the volume of NaOH required. (Basicity of H2SO

4 = 2)

(Ans - 5ml)


ii) 100g. of NaOH is dissolved in 5 litres of its solution. Find the normality of thesolution. (Ans - 0.5N)

iii) How many gram of KOH will be present in 0.1 M solution of KOH of volume500 ml. (Ans. - 2.89)

iv) Find gm/litre of 0.1 N solution of sodium hydroxide(Equivalent weight of NaOH = 40) (Ans - 4)

···


4. Current Electricity

Q. 23) Rewrite the following statement by choosing the correct option.i) The S.I. unit of potential difference is ................. (page 44)

a) Ampere b) Volt c) Ohm d) Jouleii) Electric current is measured with the help of a device called .................

(page 43)a) an ammeter b) a voltmeterc) a galvonometer d) a calorimeter

iii) ............. substance is used as insulator.a) Iron b) Copperc) Gold d) Plastic

Q. 24) Consider the relation between column (I) and (II) and fill in the column IVto match the column III.

No Column I Column II Column III Column IV pg

i) Copper Conductor Rubber – 38ii) 1 Volt 1 J/1 s 1 ampere - 43iii) Electric charge Coulomb Resistance - 44iv) –ve terminal Cathode +ve terminal - 39

Q. 25) Fill in the blanks with proper terms from the bracket :(ampere, smaller, greater, Ohms, Coloumbs, random, computer)i) The equivalent resistance of a parallel combination is .............. than the each

of the individual resistance.(pg. 53)ii) Diode does not obey .............. law.(pg. 48)iii) S.I. unit of electric current is .............. (pg. 43)iv) In conductors electrons are always in the state of .............. motion (pg 40)v) Superconductors are used in .............. (pg. 49)


Q. 26) State whether the following statement are true or false.i) Diode obeys Ohm's law. (pg. 48)

ii) A conducting wire offers resistance to flow of electrons. (pg 40)

iii) In a superconductor as temperature decreases, resistance of that materialincreases. (pg. 48)

Q. 27) Find odd one outi) Copper, Silver, Mica, Graphite (pg. 38)ii) Ammeter, Voltmeter, Galvanometer, Thermometer (pg 43)iii) Germanium, Silicon, Porcelein, Gallium. (pg. 38)

Q. 28) Give scientific reasons.i) The plates of heating devices such as a toaster, an electric iron are made of

an alloy rather than a pure metal. (pg. 45)

ii) Parallel combination of resistances decrease effective resistance of circuit.(pg. 53)

iii) Metals are good conductors. (pg. 40)


Q. 29) Distinguish between : give any two points.i) Voltmeter and Ammeter (pg. 46, 47)

ii) Resistances in series and Resistances in parallel combination. (pg. 51,52,53)

iii) E.M.F. and P.D. (pg. 49,50)

Q. 30) Draw and label the diagram :i) Atoms of hydrogen and lithium. (pg. 38)


ii) Simple Voltaic cell (pg. 39)

iii) Connection diagram of three resistances in series. (pg 51)


iv) Connection diagram of three resistances in parallel. (pg. 52)

Q. 31) Solve the following numericals.i) Calculate the potential difference (v) across a 12 ohm resistor carrying currentof 0.2 A. (Ans. 2.4 Volt)

ii) Calculate the resistance of the resistor, P.D. across two points being 4 volt andcarrying a current of 250 mA. (Ans. 16 ohm)


iii) 12 ohm and 6 ohm resistors are connected in parallel combination and 5 ohmresistance is connected in series combination with them. Find the combinedresistance. (Ans : 9 ohm)

iv) Three resistances of each 9 ohm are connected first in series combination, thenin parallel combination. Calculate their equivalent resistance in each case.(Ans. In series = 27 ohm, In parallel = 3 ohm)

N. B. For solving above numericals carefully study the illustrative examples fromself study section.

Q. 32) Define the following.i) Ampere (pg. 43)

ii) volt (pg.42)

iii) Ohm (pg. 44)

iv) Potential difference (pg. 42)

iv) E.M.F. (pg. 49)


Q. 33) Draw the symbols of the following components. (P.g. 43, Table No. 4.1)i) Resistance

ii) Electric cell

iii) Variable resistance

iv) Voltmeter

v) Closed key

vi) Tap key open

Q. 34) Obtain an expression for equivalent resistance of three resistances connectedin series combination. (pg. 51)


Q. 35) Obtain an expression for equivalent resistance of three resistances connectedin parallel combination. (pg 52, 53)

···


5. Effects of Electric Current

Q. 36) Rewrite the following statement by choosing the correct option.i) The quantity of heat generated in a conductor depends on .................

(pg. 62)a) Square of the current (I2)b) resistance of the conductor (R)c) time for which the current flows. (t)d) I2Rt.

ii) Telephone ear piece works on the principle of ................. effect of electriccurrent. (page 72)a) Magnetic b) heatingc) chemical d) optical

iii) The magnetic field produced at the centre of circular wire is directly proportionalto the ................. (pg. 69)a) radius of the loop.b) magnitude of the current passing through it.c) resistance of the wire.d) time for which the current passes through it.

Q. 37) Fill in the blanks with proper terms from the bracket :(magnetic field, 50 cycles per second, Right hand rule, Newton, calorie, area,radius)i) Heat energy produced is expressed in terms of ...............(pg. 62)ii) Orested proved that when current passes through a conducting wire it produces

...............(pg. 67)iii) The direction of the magnetic field produced by a conductor can be determined

by .............. (pg. 69)iv) In India, frequency of A.C. is .............. (pg 71)v) The magnetic field produced at the centre of a circular wire is inversely

proportional to .............. (pg. 70)Q. 38) State whether the following statements are true or false.

i) Like magnetic poles attract each other, unlike magnetic poles repel (pg. 67)ii) Fuse is made of wire having high melting point (pg 64)iii) If fire is caused by sparking, the main switch should be switched offimmediately. (pg. 74)

Q. 39) Identify the odd one of the following group.i) Geyser, Heater, Electric iron, Refrigerator (pg. 64)


ii) Magnet, Solenoid, Compass needle, Oven. (pg 71)

iii) , , , (pg. 62,63)

Q. 40) Give scientific reasons.i) Most of the electrical appliances need earthing. (pg. 74)

ii) Filament of incandescent lamp is made of tungsten. (pg. 64)

iii) Fuse is made of material having low melting point. (pg. 64)

Q. 41) Solve the following numericals.i) Calculate the heat generated in a coil of resistance 500 ohm in 30 seconds,

when 0.2 amp. current passed across it. Calculate heat in Joules. (Ans. 600 J)

I2 R t4.18

V I t4.18

V2 t4.18R

I R t4.18


ii) Calculate the heat generated in calories in a coil of resistance 418 ohm in 3minutes, when 500 mA current passes through it. (Ans. 4500 cals.)

iii) Calculate the heat generated in an electric iron, when P.D. of 209 Volts is appliedfor 2 minutes, when 0.4 amp current is passed across it. (Ans : 2400 cal)

iv) Find the resistance of 25 Watt, 240 Volt electric bulb. (Ans : 2304 ohm)

v) 80 J heat is generated in a conductor of resistance 50 ohm and time is 40 sec.Calculate the P.D. applied across it to produce above heat.(Ans. 10 Volt)


vi) Find the resistance of 60 Watt, 240 volt bulb. (Ans. 960 ohm.

Q. 42) Answer the following questionsi) What is the function of earth wire? Why it is necessary to earth metallic

appliances? (pg. 74,75)

ii) Mention any four applications of heating effects of electric current. (pg. 64)

Q. 43) State the following laws.i) Joule's law of heating effect of electric current (pg. 62)

ii) Right hand rule. (pg. 69)


Q. 44) Draw and label the diagram.i) Heating effect of electric current. (verification of Joule's law.) (pg. 61)

ii) Telephone ear piece. (pg. 73)


Q. 45) Write any two precautionsa) while using electrical appliance. (pg. 75)

b) against bad insulation (pg 74)

c) against improper earthing (pg. 74,75)

···


6. Energy Sources

Q. 46) Rewrite the following statement by choosing the correct option.i) Energy obtained from ................. is pollution free. (pg. 90)

a) Petrol b) Coal c) nuclear reactor d) solar cellii) Calorific value of ................. is highest amongest fuels. (page 97)

a) Hydrogen b) Methanec) LPG d) Biogas

iii) To remove moisture from grapes we use ................. (pg. 90)a) solar water heater b) solar cookerc) solar cell d) solar dryer

iv) A device which converts solar energy into electrical energy is known as solar................. (pg. 90)

a) Cooker b) dryerc) heater d) cell

Q. 47) State whether the following statement are true or false. Correct the falsestatementi) Children use solar energy to fly kites (pg. 81)

ii) The inner surface of solar cooker box is red (pg 88)

iii) The efficiency of chulha is less than 15% (pg. 92)

iv) Wind mills convert wind energy into electrical energy. (pg. 82)

Q. 48) Rewrite the second column so as to match the first column.Column I Column II

1) Biomass a) flowing water2) Renewable energy b) artificial satellites3) Non-renewable energy c) Forests4) solar cell d) Natural gas

(pg. no. 92,85,81,90)


Q. 49) Give scientific reasons.i) Farmers winnow the grains. (pg. 82)

ii) Solar energy is dilute source of energy (pg. 87)

iii) Windmills require specific location. (pg. 82)

Q. 50) Distinguish between.i) Renewable energy source - Non renewable energy source (pg. no. 81,82)

ii) Biomass - Biogas (pg. no. 92)


Q. 51) Draw labelled diagramsi) Solar cooker (fig. no. 9) (Pg. no. 88)

ii) Biogas (fig. no. 6.12) (pg. No. 93)


iii) Nuclear fission (fig. no. 6.11) (pg. No. 91)

···


7. Types of Energy

Q. 52) Rewrite the following statement by choosing the correct option.i) Energy ................. (pg. 101)

a) is the stored ability to do workb) can be created or can be destroyedc) cannot be convered from one form into anotherd) Exists only in mechanical form

ii) SI unit of energy is ................. (pg. no. 106)a) erg b) Newtan c) Joule d) Kw-hr

iii) ................. possesses kinetic energy.a) running water b) water in lake at sea levelc) water in a dam d) stones at the foot of hill

Q. 53) State whether the following statements are true or false. Correct the falsestatementi) Total energy of an isolated system is constant.

ii) While charging, chemical energy is converted into electrical energy. (pg 113)

iii) Potential energy is always mechanical in nature.

Q. 54) Rewrite the columns II and III so as to match the first column.Column I Column II Column III

Device/ Source Conversion of Conversion to1) Bulb Potential energy sound energy2) Dam Electrical energy Kinetic energy3) Fire crackers Chemical energy light energy


Q. 55) Give scientific reasons.i) We use pulley to draw water from the well.

ii) Water stored in dam is used to generate electricity.

iii) Electric fan blades rotate when we put on the switch.

Q. 56) Distinguish between.i) Potential energy and Kinetic energy

Q. 57)a) State the law of conservation of energy.


b) Explain the relation between joule and erg.

Q. 58) Solve the following numericals.i) A rocket of mass 100 tons is propelled vertically with velocity 1km/s. Calculate

its kinetic energy. (Ans. = 5 × 1010 J)

ii) An object of mass 10 kg is kept 10m above the ground. Calculate potentialenergy possessed by the object. (take g = 9.8 m/s2) (Ans = 980J)

···


8. Power

Q. 59) Rewrite the following statement by choosing the correct option.i) 1 HP = .................

a) 746 Watts b) 36 × 105 Jc) 1000 watts d) 1000 erg/s

ii) ................. is a scalar quantity.a) force b) velocityc) Acceleration d) power

iii) The SI unit of power is .................a) HP b) W c) Nm d) erg

iv) Power .................a) is always positive. b) can be positive or negative.c) is a vector quantity . d) cannot be added.

Q. 60) State whether the following statements are true or false. Correct the falsestatementsi) Power is the rate of performing work.

ii) All persons use the same power to climb equal heights

iii) Power used depends upon the direction of displacement in comparison to theapplied force.

iv) If a machine has more output power than another machine, it will do thework faster.

Q. 61) Solve the following numericals.i) If a 60 Watt bulb is put on for 6 hours, how much electrical energy is consumed?

(Ans. 0.36 kw.hr = 0.36 units)


ii) A 30 HP car is moving with uniform velocity of 54km/hr. Find the forword forceexerted by its engine. (Ans. 1492N)

iii) A car of mass 1000kg is driven along levelled road against a constant resistanceof 200N. The output of engine of the car is 8kW. Find the acceleration of thecar when its speed is 10m/s. (Ans = 0.6m/s2)

···


9. Sound

Q. 62) Rewrite the following statement by choosing the correct option.i) The pattern of the disturbance which travels through medium is known as

................. (Pg. 127)a) compression b) rarefactionc) wave d) sound

ii) Sound waves do not travel through ................. (pg. no. 128)a) vaccum b) air c) water d) solid

iii) The velocity of the sound in air at 00C is ................. (pg. no. 129)a) 331 m/s b) 332 m/s c) 340 m/s d) 360 m/s

iv) The velocity of sound is maximum in the ................. medium. (pg. no. 130)a) solid b) liquid c) gaseous

63) Fill in the blanks.i) In the fresh water the speed of sound is ................. m/s.ii) In sea water the speed of sound is ................. m/s.iii) In iron, the speed of sound is about .................m/s.iv) An increase in the temperature of air by 10C will increase the velocity of sound

by .............m/sv) Unit of intensity of sound is ..................vi) An increase in humidity ................. the velocity of sound in air.

(pg. no. 135, 136)Q. 64) Give scientific reasons.

i) The flash of lightning is seen from clouds before the thunder is heard althoughboth occur simultaneously. (pg. 130)

ii) Inside auditorium curtains are used. (pg. 131)

iii) Every hill station has an echo point. (pg. 132)


iv) In fairs or at tourist spots people prefer to use megaphone.

Q. 65) Write notes on.i) Causes of noise (pg. 137)

ii) Measures of noise control (pg. 137)

Q. 66)Draw labelled diagram.i) Sound waves need a medium. (pg. 128)


ii) Reflection of sound waves (pg. 131)

Q. 67) Solve the following numericals.i) A person hears a thunder 8 seconds after a flash of lightning is seen. At what

distance the lightning is struck neglecting speed of light?(Speed of sound in air is 340 m/s.) (Ans. = 2720 m.)

ii) A person observes a smoke from the cannon. After 6 seconds, he hears thebang. If the cannon is 2040 m. away from the observer, calculate the velocity ofsound in air. (Ans = 340 m/s.)

···


10. Heat

Q. 68) Fill in the blanks.i) The behaviour of the water between .................0C to ................. 0C is called

behaviour of the water. (Pg. 143)ii) Density of water is maximum at .................0C (pg. 143)iii) The dampness or moisture in air, due to water vapour content is called

................. (pg. 147)iv) If relative humidity exceeds .................% we feel that the air is moist. (pg 148)v) When the water vapour in air is condensed a ................. is formed. (pg. 148)

Q. 69) Define.i) Dew point (Pg. 147)

ii) Absolute humidity (pg. 147)

iii) Relative humidity (pg. 148)

iv) Specific heat capacity (pg. 150)

Q. 70) Draw labelled diagrams.i) Hope's apparatus (pg. 144)


Q. 71) Write short notes on.i) Anomalous behaviour of water (pg. 143, 146)

Q. 72) Give scientific reasons.i) In winter, sometimes the pipe lines carrying water burst when thetemperature of atmosphere falls below 40C (pg. 146)

ii) In cold countries rocks crumble into pieces in winter (pg. 146)

iii) Water cannot be used in thermometer (pg. 152)


iv) A white trail may be seen behind high flying aircraft. (pg. 148)

···


11. Light

Q. 73) Rewrite the following statement by choosing the correct option.i) When a glass slab is kept on the letters on a paper the letters appear to be

................. (pg. 165)a) shifted to the rightb) shifted to the leftc) raised slightlyd) shifted to the lower side

ii) The distance between optical centre and principal focus of a lens is called.................

(pg. no. 168)a) focal length b) optical axisc) radius of carvature d) centre of curvature

iii) According to cartesian sign convention ................. (pg. 174)a) all distances parallel to the optical axis are measured from principal focus.b) distances measured in the opposite direction of the incident ray of light are taken as positivec) all distances are taken as positived) distances measured in the direction of the incident ray are taken as positive.

Q. 74) Fill in the blanks.i) When a beam of white light passses through a prism ................. ray of light isdeviated most. (pg. 181)ii) Presbyopia occurs due to weakening of ................. (187)iii) ................. shaped cells of the retina are sensitive to the intensity of light.

(pg. 194)iv) Simple microscope is also called as ................. (pg. 189)v) ................. has maximum refractive index with respect to vacuum. (pg 165)

Q. 75) Give scientific reasons.i) The bottom of the water tank appears to be raised. (pg. 165)

ii) A convex lens is called converging lens. (pg. 169)


iii) Some people are colour blind. (pg 195)

iv) The distant objects appear small. (pg. 189)

v) A person suffering from myopia uses a spectacle having concave lens of suitablefocal length. (pg. 185)

Q. 76) Distinguish between the following.i) Reflection of light and refraction of light. (pg. 158, 159)

ii) Simple microscope and compound microscope. (pg. 189, 190)


iii) Converging lens and diverging lens (pg. 167, 169)

Q. 77) Solve the following numericals.(N.B. : Learn the illustrative examples given in the text book, all formulae andcartesian sign convention)i) A focal length of a lens is +20 cm. Find the power of the lens; also write the

type of the lens. (See the example given on page 188) (Ans. 5D, convex lens)

ii) An object is kept at a distance of 30 cm in front of a concave lens and its imageis formed at a distance of 20 cm from it. Find1) The focal length of the lens.2) Position of the image formed.(see the example on page 177) (Ans - f = 12, other side of the object)


iii) Two convex lenses of focal lengths 10cm and 5cm are kept in contact. Find thefocal length of the combined lens.(See the solve example on page 179) (Ans = )

iv) The refractive index of glass is 1.6 with respect to air. Find the refractive indexof air with respect to glass.(use formula 11.2 given on page 163) (Ans - 0.625)

v) The focal length of a convex lens is 30cm. An object of height 2 cm is kept ata distance of 45cm from it. Find1) Distance of the image from the lens2) height of the image3) Magnification of the lens4) Nature of the image(see the solved example no. 11.2 on page 177)(Ans. 1) 90 cm 2) 4 cm 3) 2 4) real and magnified)

103


vi) Velocity of light in air is 3 × 108 m/s. Find the velocity of light when it passesthrough a slab of flint glass having refractive index 1.6. (see the formula givenon page 163) (Ans. = 1.87 x 108)

vii) The power of the lens in 4 diopters. Find the focal length of the lens.(See the solved example on page 179) (Ans. 0.25 m or 25 cm)

Q. 78) Draw and label the diagrams.i) Refraction of light through a glass slab. (page 161)


ii) Image formed by a convex lens when an object is placed beyond 2F1

(pg. 171)

iii) Compound microscope (pg 191)


iv) Image formed by a convex lens when an object is placed on 2F1.(page 171)

v) Dispersion of light, by a prism. (pg. 182)


Q. 79) Answer in shorti) What is least distance of distinct vision? (pg. 184)

ii) Write new cartesion sign conventions. (pg. 174)

iii) What is dispersion of light? (pg. 181, 182)

Q. 80) Write short notes.i) Cataract (pg. 188)

ii) Persistence of vision (pg. 193)


iii) Power of accommodation (pg. 184)

iv) Colour blindness (pg. 195)

v) Hypermetropia (pg. 185)


Q. 81) Definei) Diopter (pg. 177)

ii) Magnification (pg. 175)

iii) Centre of curvature of a lens (pg. 167)

iv) Refraction of light (pg. 159)

v) Angle of deviation (pg 181)

Q. 82) Write the specific function of the following parts of the eye.i) Aqueous humor (pg. 183)

ii) Pupil (pg. 183)

iii) Eye lens (pg. 183)


iv) Ciliary muscles (pg. 183)

v) Optic nerve (pg. 184)

···


12. Modern Physics

Q. 83) Rewrite the following statement by selecting the correct option.i) ................. has highest penetrating power. (pg. 203)

a) α particle b) β particlec) x-rays d) gamma rays

ii) ................. is not a ratioactive element. (pg. 200)a) Uranium b) Sodiumc) Thorium d) Radium

iii) The property of radioactivity is first discovered by ................. (pg. 200)a) Enrico Fermi b) Becquerelc) Pierre Curie d) Rontgen

iv) The picture tube of television is a ................. ray tube. (pg. 204)a) alpha b) gammac) x-ray d) cathode

v) Real diamonds can be distinguished from artificial ones by observing theircharacteristics under ................. (pg 207)a) beta rays b) gamma raysc) x-rays d) alpha rays

Q. 84) Rewrite the IInd Column to match the Ist Column.

Column I Column II1) Nuclear fission a) Cancer2) x-rays b) Archaeology3) cobalt - 60 c) Source of energy4) Radio isotopes d) To detect fracture of bones5) Carbon dating e) food preservation

(see answers on pages 09, 212, 213, 207)


Q. 85) Fill in the blanks with proper term from the bracket.(x-rays, radioactivity, controlled chain reaction, P-32, half life, isotope, Nuclearfusion)

i) ................. is the time required by a given radioactive substance containingatoms to reduce to half of its number.

ii) For tracing locations of tumors ................. isotope is used.iii) ................. is the basis of atomic reactor.iv) The property of emmision of high energetic and high penetrating radiations is

known as .................(find answers on pages 211, 222, 212, 205, 210)

Q. 86) State whether the following statements are true or false. Rewrite the correctstatement.i) When a nitrogen atom is bombarded by neutrons C–14 isotope is formed.

(pg. 213)

ii) The radiation emitted by a radioactive substance and which is deflected towardsnegative plate is called β radiation (pg. 201)

iii) α particles are helium nuclei. (pg. 202)

iv) Cathode rays can produce x-rays (page 204)

v) The amount of energy equivalent to 400 MeV is liberated in fission of one Uatom (pg 208)

Q. 87) Give scientific reasons.i) X-rays are used to detect fracture of bones in the body. (pg. 206, 207)

23592

235

92


ii) Controlled chain reaction is a source of useful energy. (pg. 210)

iii) In an electric field α particles are less deflected than β particles (pg 195)

iv) X-rays are invisible. (pg. 206)

v) Cathode rays are used in Cathode ray oscilloscope. (pg. 204)

Q. 88) Distinguish between the following.i) α particles and gamma particles (pg. 203)


ii) Nuclear fission and Nuclear fusion (pg. 207, 210)

Q. 89) Draw and label the diagrams.i) Production of α, β, γ radiations (pg. 201)


ii) Production of x-rays (pg. 206)

iii) Chain reaction (pg. 209)


Q. 90) Write short notes on the following.i) Four properties of x-rays (page 206)

ii) Uses of x-rays (page 207)

iii) Uses of radio isotopes in medicine (page 212)

iv) The laws of radioactive transformation. (pg. 203)


v) Uses of cathode rays (pg. 204)

···


MAHARASHTRA STATE BOARD OF SECODARYAND HIGHER SECONDARY EDUCATION,


SUB : SCIENCE AND TECHNOLOGY : PART TWO

NAME OF THE CENTRE :

NAME OF THE CANDIDATE :

REGISTRATION NO. :

ADDRESS :

DATE OF BOOKLET RECIEVED :

DATE OF SUBMISSION :N.B.: Write the answer of each question in the space provided. If neces-sary, attach separate sheets for answer. Q. Marks Q. Marks Q. Marks Q. Marks No. No. No. No. 1 11 21 31

2 12 22 32

3 13 23 33

4 14 24 34

5 15 25 35

6 16 26 36

7 17 27 37

8 18 28 38

9 19 29 39

10 20 30 40


Q. Marks Q. Marks Q. Marks Q. Marks No. No. No. No. 41 55 69 83

42 56 70 84

43 57 71 85

44 58 72

45 59 73

46 60 74

47 61 75

48 62 76

49 63 77

50 64 78

51 65 79

52 66 80

53 67 81

54 68 82


Science and Technology Part II

Exercise Section

Chapterwise Serial numbers of questions

Sr. No. Name of the Chapter Question nos-From - to

1. Metals and Non-Metals 01 To 11

2. Compounds of Metals and

Non-Metals 12 To 20

3. Chemistry of Carboon Compounds 21 To 25

4. Food and Food Adulteration 26 To 30

5. Nutrients 31 To 34

6. Food Spoilage and Wastage 35 To 37

7. Diseases and Disorders I 38 To 43

8. Diseases and Disorders II 44 To 51

9. Dietary Deficiency Diseases 52 To 63

10. Diseases due to Overintake of

Some Nutrients 64 To 69

11. Human Health and Hygiene 70 To 75

12. Biotechnology 76 To 85


EXERCISE SECTION

1. Metals and Non-MetalsQ.1) Rewrite the statements by selecting the correct option.

1) The metal existing in the solid state at ordinary temperature is

__________ (Pg. 1)

a) mercury b) Copper c) bromine d) Chlorine

2) The electronic configuration of sodium is ________ (Pg. 2)

a) 2, 8, 4 b) 2, 8, 1 c) 2, 8, 3 d) 2, 8, 5

3) The sublimate of sulphur is called ________ (Pg. 13)

a) allotropes b) milk of sulphur c) flower of sulphur d) crown ring

4) ________ is used as a fungicide on fruit trees and grape vines.

(Pg. 14)

a) ammonia b) Carbon - dioxide c) hydrogen sulphide d) sulphur

5) _________ is the ore of aluminium.

a) bauxite b) haemetite c) Limonite d) siderite

Q.2) State whether the following statements are true or false. Rewritethe correct statement if the given statement is false.i) Hydrogen sulphide has smell of rotten eggs. (Pg. 16)

ii) Ammonia gas is collected by the upward displacement of air.

(Pg. 20)

iii) Red litmus paper turns blue in ammonium hydroxide. (Pg.21)

iv) Molten slag of iron after solidification is used for road building. (Pg. 8)

Q.3 Rewrite column II and III so as to match column I.Column I Column II Column III

i) Al2O3, 2H2O, (Pg. 4, 12)

1. Sulphur (a) Limonite ii) FeS2

2. Iron (b) Bauxite iii) 2Fe2O

3, 3H

2O

3. Aluminium (c) Pyrite


Q. 4. Give scientific reasons :1) The valency of sodium is 1 (Pg. 2)

2) Sulphur powder is dusted on fruit trees and grape vines. (Pg. 14)

3) Ammonia gas is collected in gas jar by passing it through a lime tower

(Pg. 20)

4) We can obtain a fountain of ammonia gas. (Pg. 21)

Q. 5. Distinguish between :1) Haemetite and Cryolite. (Pg. 4, 9)

2) Carbon di-oxide and Ammonia. (Pg. 19, 21)


Q. 6. Explain with the help of balanced chemical equations :1) Action of dil hydrochloric acid on zinc. (Pg. 3)

2) Copper and Sulphur are heated together. (Pg. 14)

3) Calcium oxide is treated with dilute hydrochloric acid. (Pg. 3)

4) Magnesium ribbon is burnt in a gas jar containing carboon dioxide.

(Pg. 19)

Q. 7. Write the formulae :1) Ammonium hydroxide (Pg. 21)

2) Sulphuric acid (Pg. 17)


3) Sodium meta aluminate (Pg. 3)

4) Calcium silicate (Pg. 8)

Q. 8. Write the definitions :1) Reducing agent (Pg. 5)

2) Oxidation (Pg. 3)

3) Metalloid (Pg. 2)

4) Alloy (Pg. 10)

5) Charge (Pg. 7)


9. Draw neat labelled diagrams of :1) Blast furnace (Pg. 7)

2) Kipp’s Apparatus (Pg. 16)


3) Laboratory Preparation of hydrogen sulphide (Pg. 15)

4) Laboratory preparation of ammonia (Pg. 20)


5) Ammonia fountain (Pg. 21)

Q. 10. Write the properties :1) Two chemical properties of ammonia (Pg. 21)

2) Two physical properties of sulphur (Pg. 16)

3) Two chemical properties of carbon dioxide (Pg. 18, 19)


Q. 11. Write two uses of :1) Carbon dioxide (Pg. 19, 20)

2) Sulphur (Pg. 14)

3) Ammonia (Pg. 22)


2. Compounds of Metals and Non-metalsQ. 12. Rewrite the statements by selecting the correct option.

1) _________ is used as an antacid in medicine to neutralise the acidity

in the stomach. (Pg. 28)

a) Baking soda b) washing soda c) Blue vitriol d) Bleaching powder

2) ________ is a variety of calcium carbonate

a) Glass b) Paper c) marble d) Black ink (Pg. 29)

3) Crystalline salt of copper sulphate is ______ in colour.

a) green b) white c) blue d) brown (Pg. 30,31)

Q.13 Rewrite the second column so as to match the first column.. Column I Column II

1) Sodium Carbonate a) FeSo4 7H

2O (Pg. 28)

2) Sodium bicarbonate b) Na2CO3 (Pg. 28)

3) Blue vitriol c) CuSO4 5H2O (Pg. 30)

4) Green vitriol d) NaHCO3

(Pg. 30)

Q. 14. Identify the odd one out of the group.1) Baking soda, washing soda, Benzene, Blue vitriol. (Pg. 34, 35)

2) Lime stone, Blue vitriol, Carbon-di-oxide, Plaster of Paris (Pg. 34, 35)

3) Lime stone, marble, Chalk, Mohr’s salt. (Pg. 29)


Q. 15. State whether the following statements are true or false. Rewritethe correct statement if the given statements is false.

1) Burnt alum is used as an ingredient in medicines. (Pg. 32)

2) Mohr’s salt is used in Daniel Cell. (Pg. 30, 31)

3) Plaster of Paris is prepared by heating gypsum. (Pg. 32)

Q. 14. Give scientific reasons.1) On heating crystaline copper sulphate, white anhydrous copper sul-

phate forms. (Pg. 31)

2) Plaster of Paris is used in making statues. (Pg. 33)


3) Due to Ferrous sulphate, acidified potassium permanganate solution

of purple colour becomes colourless. (Pg. 30)

Q. 17. Distinguish between the following pairs.1) Green vitriol and Blue vitriol (Pg. 30)

2) Lime stone and alum (Pg. 29, 31)

Q. 18. Write balanced equations for the following reactions.1) Potash alum heated strongly. (Pg. 32)

2) Reaction of baking soda with hydrochloric acid. (Page 28)


3) Gypsum is heated. (Pg. 32)

Q. 19. Write two uses of each of the following.1) Lime stone (Page 30)

2) Green vitriol (Page 30)

3) Bleaching powder (Pg. 33)

Q. 20. State any two properties of the following.1) Plaster of Paris (Pg. 32)

2) Washing Soda (Pg. 28)

3) Sodium bicarbonate (Pg. 28)


3. Chemistry of Carbon CompoundsQ. 21. Rewrite the second column so as to match the first column.

Column I Column II1) Alkane a) C3

H6 (Pg. 40)

2) Alkene b) Cn H2n-23) Alkyne c) Cn H2n+24) Cyclopropane d) Cn H2n

e) C6 H6

Q. 22. Write the definitions.1) Catenation (Pg. 38)

2) Homologus series (Pg. 41)

3) Unsaturated hydrocarbon (Pg. 40)

4) Polymerization (Pg. 43)


5) Global warming (Pg. 42)

Q. 23. Write short notes :1) Petrochemicals (Pg. 42)

2) Green house effect (Pg. 42)

Q. 24. Give the commercial importance.1) Methane (Pg. 43)

2) Methyl alcohol (Pg. 43)


3) Acetaldehyde (Pg. 43, 44)

4) Acetic acid (Pg. 44)

25. Answer briefly :1) Give the classification of hydrocarbons. (Pg. 40)

2) Explain the reaction of Polymerisation. (Pg. 43)


4. Food and Food AdulterationQ. 26. Complete the following table.

Food Stuff Adulterant1) ----------- a) Paper pulp

2) Mustard oil b) ---------------

3) ----------- c) Dried papaya seeds

4) Coffee d) ---------------

Q. 27. Fill in the blanks.1) Each cell is made up of different _______ (Pg. 47)

Such as proteins, nucleic acid etc.

2) Carbohydrates and _______ are energy rich foods. (Pg. 51)

3) If turmeric coated with ______ is consumed toxic symptoms of

lead poisoning are seen. (Pg. 56)

4) The ultimate source of energy for all living system

is _______ (Pg. 48)

Q. 28. Write the definitions :1) Growth of a body (Pg. 48)

2) food (Pg. 48)

3) Balanced diet (Pg. 51)


4) Food adulteration (Pg. 53)

Q. 29. Answer briefly :1) Write the important functions of water in the body. (Pg. 52)

2) Write a note on ‘Epidermic Dropsy. (Pg. 56)

3) Measures undertaken by the Government to prevent food

adulteration. (Pg. 55)


Q. 30. Give scientific reasons :1) Food should always be kept well - covered. (Pg. 53)

2) Requirement of balanced diet may be different for different

people. (Pg. 51)

3) Kesari Dal is soaked in; for several changes of hot water. (Pg. 56)


5. NutrientsQ. 31. Fill in the blanks.

1) _________ is the rich source of sucrose sugar. (Pg. 62)

2) Most of the proteins act as ________ in the cell. (pg. 63)

3) Vitamin ______ plays an important role in vision. (Pg. 66)

4) Vitamin A is also known as _____ (Pg. 67)

Q. 32. Find the odd one out.1) Vitamin A, D, C and K (Pg. 66)

2) Rice, moong, wheat, bajra. (Pg. 62)

3) Coconut, groundnut, almond, sugarcane. (Pg. 65)

Q. 33. Give scientific reasons.1) Our daily diet should contain water soluble vitamins. (Pg. 68)

2) Our diet should contain food with insoluble fibres. (Pg. 63)


3) Every person should drink sufficient amount of water. (Pg. 69)

Q. 34. Answer the following : .1) Write the important functions of proteins (Pg. 64)

2) Give the importance of iodine in our diet. (Pg. 71)

3) Give the important functions of phosphorus. Mineral nutrient.

(Pg. 70)


6. Food spoilage and WastageQ. 35. Define the following.

1) Food spoilage (Pg. 76)

2) Pasteurisation (Pg. 80)

3) Putrefaction (Pg. 78)

Q. 36. Write short answer.1) Name the factors affecting growth of micro organisms (Pg.77,78)

2) Give the types of undesirable changes in food. (Pg. 76)


3) How food is spoiled due to improper handling. (Pg. 82)

Q. 37. What is meant by food spoilage ?

What are the causes of food spoilage ? (Pg. 77)


7. Diseases and Disorders - IQ.38. Rewrite the statements by choosing the correct option :

i) __________ showed that the cause of anthrax was bacteria.(Pg. 88)a) Louis Pasteur b) Mac Mahon c) Paugh d) Robert Koch(Pg. 88, 89)

ii) Chickunguniya is caused by _______a) bacteria b) virus c) algae d) fungus

iii) 1 Micron = ________ m (Pg. 92, 93)a) 1000 b) 106 c) 10-6 d) 10-3

Q.39. Give scientific reasons.i) Uncontrolled rate of division of cells is dangerous. (Pg. 92)

Q.40. Only write the name of the disease : (Pg. 89-92)i) Caused by snail ii) Caused by virus

iii) Caused by bacteria iv) Caused by protozoa

v) Caused by cold (winter) vi) Caused by fungus

Q.41. Answer briefly :i) Write the symptoms of Mongolism. (Pg. 95)


ii) Which important part of the body is affected by sickle - cellanaemia ? Why ? (Pg. 94)

iii) What is meant by ‘Genetic diseases’ ?Write the symptoms of one such disease. (Pg. 94)

iv) What precautions will you take to prevent water - bornediseases? (Pg.93)

Q.42. Write the definitions :i) Disease (Pg. 88) ii) Epidemological triad. (Pg. 89)

iii) Illness (Pg. 88) iv) Sickness (Pg. 88)

Q.43. i)Name the two types of tumours (Pg. 92)


ii) What is ‘droplet nuclei’ ? Explain briefly. (Pg. 92, 93)


8. Diseases and Disorders - IIQ.44. Rewrite the statements by choosing the correct option

i) Wearing of tight clothes may lead to ________ (Pg.101)

a) Leprosy b) Cancer c) Hepatitis d) Ascariasis

ii) There is no vaccine for _______ (Pg.107)

a) HAV b) HBV c) Cancer d) Typhoid

iii) There is no cure for the disease ________ (Pg.105)

a) HAV b) Malaria c) HBV d) Typhoid

Q.45. Rewrite the second column so as of match the first column-

Column A Column Bi) Kaposi’s sarcoma a) Ascariasis

ii) Yellow eyes b) Cancer

iii) lnsensitive patch c) HAV

iv) Stomach pain d) AIDS

v) Uncontrolled cell division e) Leprosy

Q.46. Give scientific reasons :i) One should follow habits of cutting nails regularly (Pg. 104)


ii) One should avoid sharing toothbrushes and clothes. (Pg. 105)

iii) One should avoid immoral sexual contact. (Pg. 105)

iv) Before blood transfusion, the blood must be checked for HIV.

(Pg. 108)

Q.47. Draw a neat, well-labelled diagram of the structure of HIV.(Pg. 106)


Q.48. Answer briefly :

i) Which factors are responsible for cancer ? (Pg. 100, 101)

ii) Explain the two main types of leprosy. (Pg. 101)

iii) Explain the three stages of malaria. (Pg. 103)

iv) Write the symptoms of ascariasis. (Pg. 103, 104)

v) Write the minor signs of AIDS (Pg. 107)


vi) How does the transmissions of HBV virus take place ? (Pg. 105)

vii) Which drugs should be taken for prevention/Suppression of

the malaria ? (Pg. 103)

Q.49.i)Write the control and preventive measures of leprosy. (Pg. 102)

ii) How can ascariasis be prevented ? (Pg. 103)


iii) Name two examples of communicable diseases. Write their

preventive measures. (Pg. 104)

Q.50. Why should everyone be aware of their sexual behavior ?

(Pg. 108)

Q.51. Write short notes :i) Three stages of Leprosy (Pg. 102)


ii) Three stages of Malaria (Pg. 103)

iii) Antihelminth Drugs (Pg. 104)

iv) Treatment for Malaria (Pg. 103)


9. Dietary Deficiency DiseaseQ.52.Fill in the blanks from the words given in the bracket.

i) In Kwashiorkor, the swollen belly is due to the enlargement of

_________ (Pg. 113)

ii) In Marasmus, ________ face does not occur. (Pg. 114)

iii) The decrease in ______ level in the body causes muscular

cramps. (Pg. 116)

iv) Dental caries occur due to deficiency of _______ (Pg. 118)

v) Deficiency of vitamin ______ leads to blood clotting. (Pg. 120)

[K.E., liver, sodium chloride, moon, fluorine]

Q.53. Rewrite the second column so as to match the first columnColumn A Column B

i) Kawashiorkor a) Rickets

ii) Deficiency of Vitamin A b) Moon face

iii) Marasmus c) Growth retardation

iv) Deficiency of Thiamine d) Night blindness

v) Deficiency of Vitamin D e) Beriberi

f) Dental caries


Q.54. Give scientific reasons :i) It is essential to eat fatty substances so that vitamin-A proves

useful to the body. (Pg. 118)

ii) Deficiency of Vitamin K does not occur normally. (Pg. 120)

iii) Deficiency of iron leads to anaemia. (Pg. 117)

iv) Deficiency of calcium and phosphorous in adult leads to osteo-

malacia. (Pg. 116)

Q.55. Give the difference between : Kwashiorkor and Marasmus.

(Pg. 114)


Q.56.Name the disease caused due to the following deficiencies :(Pg. 113 to 120)i) Proteins ii) Vitamin C iii) Vitamin D iv) sodium

v) Molybdenum vi) Thiamine viii) Niacin viii) Vitamin K

ix) Vitamin E x) Fluorine

Q.57.Give the definitions : (Pg. 112)i) Balanced diet ii) Malnutrition


Q.58.Which are the four types of malnutrition. Explain each briefly.

(Pg. 121)

Q.59.Explain how social factors are responsible for malnutrition.

(Pg. 122)

Q.60.Which programmes are initiated by the Government of India for the

enrichment of food ? (Pg. 123,124)

Q.61.Why are aerated drinks harmful ? (Pg. 124)


Q.62.Give two examples of each : (Pg. 116 to 125)i) Fast food ii) Non-fermented drinks

iii) Aerated drinks iv) Cooking practices

v) Protein enriched food vi) International committees

vii) Diseases caused due to deficiency of copper

viii) Organs affected by deficiency of Iodine.

Q.63.i) Give the symptoms of anaemia (Pg. 117)

ii) Which disease is caused by deficiency of iodine ? (Pg. 118)

iii) Name five trace elements. (Pg. 117)

iv) Give four causes of iron deficiency. (Pg. 117)


10. Disease due to Overintake of Some NutrientsQ.64.Rewrite the statement by selecting the correct option.

i) Broca Index = __________ (Pg. 131)

a) weight/Height2 b) weight/height c) Height (m) - 100

d) 100 - Height (cm)

ii) Diabetes is _______ deficient disease. (Pg. 131)

a) sugar b) Carbohydrates c) insulin d) Proteins

iii) About _____ % of fluorine is found in bones and teeth. (Pg. 134)

a) 90 b) 80 c) 69 d) 96

Q.65. According to the given property identify the odd one out.1)

a) hypertension

b) diabetes Insulin deficient (Pg. 138)

c) Coronary heart disease disease

d) atherosclerosis

2)a) Vitamin A the one which is (Pg. 138)

b) Vitamin B not fat soluble

c) Vitamin D

d) Vitamin K

3)a) arterioselerosis disease not related

b) hypertension with excessive intake (Pg. 138)

c) dental fluorosis of fat

d) coronary heart disease


4)a) headache symptom of

b) delayed healing wound diabetes (Pg. 138)

c) fever

d) cough

5)a) weight reduction responsible factor

b) regular physical activity for hypertension (Pg. 138)

c) dental fluorosis

d) habitual smoking

Q.66. Give scientific reasons.1) Diabetes is insulin deficient disease. (Pg. 131)

2) Hypertension of any type is harmful to body health. (Pg. 133)


3) Smoking should be avoided. (Pg. 134)

Q.67. Definei) Body mass index (BMI) 2) Hypertension (Pg. 130, 133)

Q.68. Write short answersi) Give the main symptoms of diabetes. (Pg. 132)

ii) What is arterioscleroisis ? Which precautions should be taken to

avoid arterioscleroisis ?

iii) State the prevention of hypertension. (Pg. 133)


iv) What are the causes of coronary heart disease ? (Pg. 133)

v) Give symptoms of dental fluorosis ? (Pg. 134)

Q.69. Write short notes on -a) Hypervitaminosis of vitamin A. (Pg. 135)

b) Give the disadvantages of excessive nutrient intake. (Pg. 135)


c) Obesity. (Pg. 130)


11. Human Health and HygieneQ.70.Rewrite the statements by selecting the correct option.

1) The air pollutants like _______ causes pneumonia.

a) sulphur dioxide b) Carbondioxide c) Methane

d) Hydrogen sulphide

2) The entry and development or multiplication of an infectious agent

in the animal’s body is called ______

a) Control b) Prophylaxis c) infection d) pollution

3) _______ is a process that informs motivates and helps people to

adopt and maintain healthy practices and life styles. (Pg. 147)

a) proper education b) population education

c) health education d) Hygiene

Q.71. Rewrite the second column so as to match the first column.Column I Column II

i) Ecological concept a) an understanding of health

ii) Biomedical concept b) Synthesis of all the concepts

of health

iii) Psychosocial concept c) equilibrium between man and

environment.

iv) Holistic concept d) health is biological and social

phenomenon.

v) Changing concept e) absence of disease (Pg. 140)


Q.72. Form pairs from the group of words/phrases having samerelationship.i) Educational measures ii) Population control measures

iii) Infectious under risk iv) immunization

v) Inclusion of population education vi) Direct measures

vii) Monetary gains to people viii) Sterilization operation

(Pg. 148)

Q.73. State whether the following statement are true or false.Rewrite the correct statement, if the give statement is false.i) The minimum age for marriage is 15 years for girls. (Pg. 148)

ii) Anger should be controlled by an exercise or walk. (Pg. 144)

iii) Primary health approach has been described as health by the

people and placing people’s health in peoples hands. (Pg. 142)

iv) WHO defines health as the condition of being sound in body,

mind or spirit, especially freedom from physical diseases or pain.

(Pg. 141)


74) Give scientific reasons.i) Smoking and chewing of tobacco is harmful to health. (Pg.144)

ii) Body should be rubbed with certain vegetable oil. (Pg.144)

iii) In hot weather light or white colour clothes are suitable.(Pg.145)

Q.75) Write short notes oni) Prophylaxis against infectious diseases. (Pg. 146)

ii) Need of health service research. (Pg. 143)


12. BiotechnologyQ.76.Rewrite the statement by selecting the correct option.

i) Fern pteris vittata absorbs _______ from soil.

a) Arsenic b) Selenium c) Copper d) Iron

ii) Phenylketonuria (PKU) is caused by defect in gene in ______

cells.

a) liver b) somatic c) sperm cells d) pancreas

iii) _______ is required to produce interferon.

a) blood of horse b) bacteria c) lot of human blood d) vaccine

iv) Genetically engineered produced potatoes ______ diseases

causing bacteria. (Escherichia coli) Produce protein.

a) Cholera b) interleukin c) factor VIII d) Interferon.

v) Protein ______ is used for haemophilia disease.

a) somatostatin b) interleukin c) interferons d) factor VIII

(See Pg. No. 156, 156, 155, 155, 154)

Q. 77. Rewrite the column II so as to match column I.Column I Column II

i) Herbicides a) haemophilia

ii) Transgenic potatoes b) liver of animal

iii) Factor VIII c) group of proteins

iv) Insulin d) glyphosphate

v) Interferon e) Bacteria of cholera

(See Pg. No. 153, 155, 154, 151, 155)


Q. 78. Form pairs from the group of words/phrases having samerelationship.i) Insulin ii) Haemophilia iii) Somatostatin, iv) Diabetes

v) Dwarfism vi) anaemia vii) Factor VIII viii) Erythropoietin

ix) liver x) Phenylketonuria (PKU)

For example - vi) liver - Phenyl ketonuria

(See Pg. No. 154)

Q.79. Give Scientific reasonsi) Waste water is treated before its release. (Pg.156)

ii) Transgenic potatoes cannot be cooked. (Pg.155)

iii) Hereditary diseases are non curable. (Pg.155)


iv) Transgenic tobacco is developed at Indian Institute of Science,

Bangalore. (Pg.155)

v) In earlier days, the insulin was very costly and put out of reach

of to middle class people.

(Pg. No. 156, 155, 155, 155, 151)

Q. 80) Write short notes on (Pg.155)

(i) Edible vaccines

(ii) Waste water treatment (Pg.156)


(iii) Biotechnology in agriculture (Pg.153)

(iv) Vaccination (Pg. 154, 155)

(v) Biotechnology and health

(Pg. No. 155, 156, 153, 154, 155, 154)

Q. 81) Write short answeri) State the components of DNA molecude. (Pg. 152)


ii) What problems are solved by microbial biotehnology ?(Pg.155)

iii) State the purpose for which especially pseudomonas bacteria

are useful. (Pg.156)

iv) Why genetically engineered bacterium Escherichia Coli cannot

be used to produce interferons?

v) What causes phenylketonuria (PKU) ? (Pg.155)

(See Pg. No. 153, 156, 155, 156, 156)


Q.82) Define the following terms (any two) (Pg.154)

i) Vaccination

ii) Transgenic potatoes (Pg.155)

iii) Somatic cells (Pg. 156)

iv) Gene (Pg.153)

v) Bio-remediation

(See Pg. No. 154, 155, 156, 153, 156)

Q. 83) Write the names1) The improved varieties of new mustard developed by Indian

Agriculture Research Institution. (Pg.154)

2) Write the names of two herbicides. (Pg.153)

3) Write four fields of modern biotechnology. (Pg.156)


4) Write the names of components of DNA molecule.

5) Write 4 names of plants which stores the minerals (metals) in it.

Q. 84) Write the brief notes oni) Vaccination

ii) Describe in detail the experiment carried out by Frederick Griffith.

(Pg. No. 154 - 155, 151 - 152)


Q. 85) Write brief answeri) Explain the advantages of biotechnology in agriculture.

ii) Explain with suitable example - Many of the environmental

problems can be solved using modern biotechnology.

(Pg. No. 153, 156)

X swad science

Education

Transcript of X swad science