M.C - CHEM EARTH

7/30/2019 M.C - CHEM EARTH

1/23

ANSWER IS C


2/23

ANS- A

Few elements that are found uncombined in the

lithosphere are:A. gold, sulfur and carbon

B. silicon, carbon and hydrogen

C. Quartz, silicon, oxygen

D. Sodium, potassium and silicon.


3/23

ANS- A


4/23

ANS- B


5/23

ANS - B


6/23

ANS - D

Which of the following techniques would be

the most suitable for separating dissolved

solids in liquids?

sedimentation

fractional distillation

adding a solvent then filtration

evaporation


7/23ANS- 4

Aluminium hydroxide is a solublecompound. If 1 mole of aluminium

hydroxide was dissolved in water, whatwould be the total number of moles ofions present in the solution?

1 2

3

4


8/23

ANS - A

Elements with low ionisation energies

readily form:

positive ions

negative ions

covalent compounds

radicals


9/23

ANS - B

Generally in chemical reactions, bonds are broken

in reactant molecules and new bonds are formed to

make the product molecules. When bonds areformed in a chemical reaction:

A. energy is absorbed

B. energy is released

C. energy is either absorbed or released

D. energy is both absorbed and released


10/23

ANS- B

Which of the following correctly shows the Lewis electrondot structure of hydrogen sulfide?

A H : S : H

. .

B H : S : H. .

. . . . . . C : H : S : H :

. . . . . .

D HSH


11/23

Ans - D

One mole of atomic silver, Ag, contains

A. 4 neutronsB. 2 molecules

C. 8 grams

D. 6.02 10 23 atoms


12/23

C

Which one of the scientists below is credited

with the development of the modern Periodic

Table?

(A) Dalton

(B) Rutherford

(C) Mendeleev

(D) Gay-Lussac


13/23


14/23

ANS-A

The names (i) alkali metals and (ii) halogens

are those which are given to, respectively:

A the elements in Groups I and VII.

B the elements in Group I and the first

period.

C any of the elements which react to form

ionic bonds.

D Group I and Group VIII.


15/23

ANS- B

When a non-metallic element such as sulfurreacts with another non-metallic element

such as chlorine, the bond between the twoelements is:

A an ionic one.

B a covalent one.

C extremely weak because the two elementsare non-metals.

D similar to the bond formed when sodium

reacts with chlorine.


16/23

ANS - C


17/23

ANS - D

Th t bl b l h i f ti b t th


18/23A

The table below shows some information about the

percentage of water and its state in one 'sphere' of

earth. Percentage of 'sphere' composed of water - 70%

State of water - liquid.To which one of the following spheres does the

information in the above table refer?

Hydrosphere

Atmosphere

Biosphere (living things)

Lithosphere


19/23

C

Which one of the following properties most

directly affects the reactivity of a metal?

A malleability

B melting point

C first ionisation energy

D electrical conductivity

Element Melting Point Boiling Point Density Electrical


20/23

Element Melting Point

(oC)

Boiling Point

(oC)

Density

(g/cm3)

Electrical

Conductivity

(-1m-1)

M 1410 3267 2.03 10-3

N 1064 2808 19.3 44

O 114 184 4.95 10-13

P 3974 4830 2.26 0.07


21/23

B

Which one of the four elements above is the

only metal?

(A) M

(B) N

(C) O

(D) P


22/23

B

In which one of the following substances

would you expect to have only dispersion

forces acting?

(A) H2S

(B) CH4

(C) NH3

HCl


23/23

C

Which one of the following statements about thePeriodic Table is correct?

(A) Electronegativity increases both across a period anddown a group.

(B) Atomic radius increases as the atomic numberincreases.

(C) The trends in melting points for metals and nonmetals down a group are opposite to each other.

(D) The reactivity of an element is directly related to

its electronegativity

M.C - CHEM EARTH

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