Namma Kalvi - motherindiaschool.ac.in

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CaO + SiO2 CaSiO3

Flux Slag

5. What type of ore is concentrated in froth floatation process ?

• Sulphide ore is concentrated. Galena – PbS

6. Explain the refining of Nickel by Mond’s Process

• Nickel is refined by Mond’s process in two steps

Step –I

Ni + 4 CO 350K Ni(CO)4

Impure metal Nickel Tetra carbonyl

Step – II

Ni(CO)4 460K

Ni + 4 CO � � � � � � ��pure metal

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� � Al2O3 � � 2Al+3 + 3O–2

2O–2 O2 + 4e– �

Al+3 + 3e– Al

10. Define Gangue Non metallic impurity, Silicon impurity and rock present in the ore is called as Gangue. ��

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12. Define Slag Lime stone reacts with silica to form calcium silicate called as Slag

CaO + SiO2 CaSiO3

Flux Slag

13. What are the requirements (conditions ) vapour phase refining

• The metal should form a Volatile compound with the reagent.

• The volatile compound decomposes to give the pure metal. 14. Explain the role of the following in the process mentioned.

a) Silica in the extraction of copper.

Ferrous oxide combines with silica and removed as Ferrous silicate called as Slag. FeO + SiO2 FeSiO3

Slag

b) Cyrolite in the extraction of Aluminium

It helps to lower the melting point of the mixture.

c) Sodium cyanide in froth floatation.

Sodium cyanide acts as a depressing agent which prevents other metal sulphides from coming with the froth.

15. Define Anode mud

During electrolysis the less electropositive impurities settles at the bottom of the container. These are called as Anode mud.

16. Explain the principles of electrolytic refining with a example ( Explain the electrolytic refining of Silver )

• Anode – Impure Silver

• Cathode – pure Silver

• Electrolyte – Silver nitrate + nitric acid

• Pure Silver is deposited at the cathode.

At the anode

Ag Ag+ + 1e–

At the cathode

Ag+ + 1e– Ag

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17. What are the Observations of Ellingham diagram

• The formation metal oxides gives a positive slope. The value of �S value is negative and the randomness decreases.

• The formation of Carbon monoxide gives a negative slope. The value of �S value is positive. So Carbon monoxide is more stable at high temperature

• For MgO, due to phase transition, there is a sudden change in the slope at a particular temperature.

18. What are the applications of Ellingham diagram

• The Ellingham diagram for the formation of Ag2O and HgO is at the upper part of the diagram. So, these oxides are unstable and decompose on heating.

• Ellingham diagram is used to predict the thermodynamic feasibility of reduction of metal oxides by another metal. Ex. Aluminium can be reduce Chromic oxide.

• Carbon line cuts the line of many metal oxides. Hence it can reduce all metal oxides a high temperature

19. What are the limitations of Ellingham’s diagram

• It does not explains the rate of the reaction

• It does not explain the possibility of other reactions taking place.

• When the reactants and the products are in equilibrium, the value of �G is not true value.

20. Explain the Electro chemical principles of metallurgy.

• Gibbs free energy is given by �G = – nFE

n=number of electrons F = faraday and E = Emf

• If �G is negative and E is positive then the reaction is spontaneous.

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21. How Titanium is refined by the Van-Arkel method

Ti + 2 I2 550K TiI4

TiI4 1800K

Ti + 2 I2

22. Explain the Gravity separation or Hydraulic wash process

• The ore is finely powdered and washed with a current of water.

• The lighter gangue particles are washed away by water.

• Example: Oxides ores like Tin Stone

23. Define Roasting

The Ore is oxidised by heated in the presence of Oxygen in a furnace below the melting point of the metal.

2 ZnS + 3 O2 2 ZnO + 2 SO2

24. Define Calcination

The ore is heated in the absence of oxygen in a furnace. The water molecules are removed as moisture.

CaCO3 CaO + CO2

25. Define Smelting

The ore is heating above the melting point in the presence of Flux and reducing agents like Carbon in a smelting furnace. The water molecules are removed as moisture.

Fe2O3 + 3CO 2 Fe + 3 CO2

FeO + SiO2 FeSiO3

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26. Explain the Froth Floatation process

• Frothing agent = Pine oil

• Collector = Sodium Ethyl Xanthate

• Depressing agent = Sodium cyanide

• Example = Sulphide ore = Galena

• The ore is finely powdered and mixed with water and pine oil.

• When air is passed, it produces froth.

• The ore particles rise to the surface and collected separately.

• The Impurities settles at the bottom of the container. Diagram.

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'��<��4��=>�� O2 + 2 H2O�� 4 [Au(CN)2]¯1 + 4 OH

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2 [Au(CN)2]¯ 1 + Zn [Zn (CN)4]¯2 + 2Au

Gold is reduced to Elemental gold. This is called as Cementation. �

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Gold is reduced to Elemental gold. This is called as Cementation.�

�2 [Au(CN)2]¯ 1 + Zn [Zn (CN)4]¯2 + 2Au

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31. Define Blister copper

When metallic copper is solidified, SO2 gas is evolved. And gives a blister like appearance. This is called as blister copper.

32. Explain the Alumino thermite process ( Metal reduction )

• Chromic oxide is mixed with Aluminium powder and heated in a fire clay crucible.

• A ignition mixture of Barium peroxide and Mg powder is placed over it.

• When ignited, large amount of heat is produced and Aluminium reduces Chromic oxide.

BaO2 + Mg BaO + MgO

Cr2O3 + 2Al 2Cr + Al2O3

33. Explain the Auto reduction reaction

HgS + O2 Hg + SO2

34. List the used of Aluminum ( Al)

• Aluminum foil is used for packing food items

• Aluminium is used to make cooking vessels

• Aluminum alloy is used to make Aero planes

• Aluminium is used to make gas pipes

• Aluminium is used to make electric cables

35. List the used of Iron (Fe)

• It is used to make Bridges and cycle chain

• It is used to make pipes and valves

• The alloys of iron is used to make Magnets

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36. List the used of Copper ( Cu )

• It is used to make coins

• It used to make wires and water pipes

• Copper and gold are used to make ornaments

37. List the used of Gold ( Au )

• It is used to make coins

• Copper and gold are used to make ornaments

• It is used as catalyst

• It is used in electro plating of watches.

38. Define Distillation

In this method the impure metal is heated, evaporated and the pure vapours are condensed. Ex. Zinc is distilled at 1180K

39. Explain Liquation • This method is used to remove high melting point impurities from low

melting point metals. Ex. Lead

• The impure metal is heated in the absence of air in a sloping furnace.

• Pure metal melts and flows down . And collected separately.

• The impurities remain on the slope.

40. Explain the reduction using carbon

The ore is heated with coke in a blast furnace.

ZnO + C Zn + CO

41. Explain the extraction of Copper

• Ore – Copper pyrites Concentration – Froth Floatation

Roasting -

2 (CuS.Fes) + O2 Cu2S + 2 FeS + SO2

2 Fes + 3 O2 2 FeO + 2SO2

Smelting –

FeO + SiO2 FeSiO3

Cu2S + 6 CuO 6Cu + SO2

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1. Why the first element in the P-block show anomalous properties

• It is smaller in Size

• It has high Ionisation energy and high electro negativity

• It do not have D-orbital in the valence shell

2. What are the anomalous property of first element in the P-block

a)Boron -13th group

• Boron is a metalloid

• Boron shows diagonal relationship with silicon

• The Hydrides of Boron and Silicon are Covalent compounds

• The Halides of Boron and Silicon are easily hydrolyzed

• The Oxides of Boron and silicon are acidic in nature

b)Carbon – 14th group

• Carbon is a non-metal

• Carbon forms multiple bonds like C=C and C=O.

• Carbon has a greater tendency to form Catenation.

c)Nitrogen -15th Group

• Nitrogen forms multiple bonds like N=N and N=O.

• Nitrogen is a diatomic molecule

d)Oxygen -16th Group

• Oxygen is a diatomic molecule

• Oxygen form hydrogen bonds

e)Fluorine -17th group

• Fluorine is the most electro negative atom

• Fluorine forms only -1 oxidation state

• Fluorine form hydrogen bonds

• Fluorine is a strong oxidising agent

• Fluorine is the most reactive halogen

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3. Explain the Allotropism of Carbon

• Some elements have different crystalline forms but same physical properties. This is called as Allotropism.

• Ex. Diamond, Graphite, Graphene and Carbon nano tubes.

4. Give a method to prepare Diborane from BF3

Boron tri fluoride is heated with Sodium hydride at 450K to give Diborane.

2 BF3 + 6 NaH 450K B2H6 + 6 NaF

5. Give the uses of Borax

• It is used in the identification of Coloured Metal ion

• It is used to prepare Enamels and Glass

• It is used as Flux in metallurgy

• It is used as a good preservative

6. What is Catenation. And explain the conditions of Carbon. Catenation is the ability of a element to form chain of atoms. Conditions for catenation.

• The valency of the elements should be greater than 2

• The elements should gave the ability to bond to itself

• The self bond should be a strong bond.

• Kinetic inertness of the compound towards other molecules

7. What is Fisher Tropsch synthesis ?

Carbon monoxide reacts with Hydrogen at 500k and 50atp to give hydro carbons

n CO + 2n H2 50 Atp/500K CnH2n + n H2O

8. Give the structure of CO and CO2. a) CO molecule.

• Shape = Linear

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b) CO2 molecule.

• Shape = Linear

9. Give the uses of Silicones

• Making water proof clothes

• Uses as Insulating material for electric motors.

• Making Chemical and Damp resistant Paints.

• Used in High temperature Oil Baths and Vaccum Pumps

10. AlCl3 behaves as Lewis acid. Explain the statement.

It forms addition compounds with Ammonia. Ex. AlCl3. 6 NH3.

11. Explain the structure of Diborane.

• The two BH2 units are linked by two Hydrogen Bridges.

• It has Eight B-H bonds and 12 Valence electrons.

• The Four B-H bonds are normal covalent bonds. (2c-2e- bond)

• Remaining four electrons are used to form two Bridge B-H-B bonds. It is called as Three center two electron bond.

• The Boron atom is sp3 hybridised.

• The B-H-B bond is formed by the overlapping of the half filled hybridised orbital of the one Boron, half filled 1s orbital of hydrogen and a empty hybridised orbital of another Boron.

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12. Explain Hydro Boration

The addition of Diborane with alkenes in the presence of Ether at room temperature is called as Hydro Boration.

B2H6 + 6 R-CH=CH2 2 B ( R -CH2-CH2- )3

13. Explain the metallic property of P-block elements

• Down the group the Metallic property increases.

Group Non metals Metalloid

Group -13 Boron

Group -14 Carbon Si and Ge

Group -15 Nitrogen and Phosphorous As and Sb

Group -16 Oxygen, S and Se Tellurium

Group -17 All are non metals

Group -18 All are non metals

14. How will you identify the Borate radical ?

When borate radical is heated with ethyl alcohol and sulphuric acid it gives Tri alkyl borate which burns with a Green edge flame.

4 H3BO3 + 3 C2H5OH H2

SO4 B(O C2H5)3 + 3 H2O

15. Write a short notes on Zeolite • Zeolites are three dimensional crystals containing Aluminium, Silicon

and Oxygen.

• They are Sodium Alumino Silicates.

• It has a porous structure where the sodium ions and water molecules are loosely held.

• The Silicon and Aluminium atoms are tetrahedrally bonded through a oxygen atom.

• Zeolites have the honey comb structure with tunnels and cages.

• Water molecules can freely move in and out of these pores.

• Zeolite acts as Molecular Sieve.

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16. CO ( carbon monoxide ) act as reducing agent. Prove ?

3CO + Fe2O3 2 Fe + 3 CO2

17. Give the Laboratory preparation of Carbon di oxide

CaCO3 + 2 HCl CaCl2 + CO2 + H2O

18. Define Inert Pair effect.

In P-block, the pair of S-electrons becomes chemical inert and do not take part in bonding. This is called as Inert pair effect.

19. What are the uses of Boron

• Boron = Used as Rocket fuel igniter

• Boron = Present in cell wall of plants.

• Boron = Neutron absorbers in nuclear reactor.

• Boric acid = Eye drops Antiseptic and Washing powder.

20. Give the preparation of Borax When Colemanite is boiled with sodium carbonate solution it gives Borax.

2 Ca2B6O11 + 3 Na2CO3 + H2O 3 Na2B4O7 + 3 CaCO3 + Ca(OH)2

21. Give the action of heat of Borax

Na2B4O7 . 10 H2O —10 H2O Na2B4O7 2 NaBO2 + B2O3

22. Give the action of heat of Boric acid

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23. Explain the structure of Boric acid

• Boric acid has a two dimensional layer structure

• It has [ BO3] —3 units bonded by hydrogen bonds.

24. What are the used of Boric acid.

• Used to prepare glass, pigment and enamels

• Used as antiseptic and eye lotion

• Used as food preservative

25. Give the preparation of Borazole or Borazine

( Inorganic benzene ) ( Action of Diborane with Ammonia )

3 B2H6 + 6 NH3 High T 2 B3N3H6 + 12 H2

26. List the used of Diborane

• Used as High energy fuel for Propellants

• Used as reducing agent in organic chemistry

• Used in welding.

27. Give the Lab preparation of Boron Tri fluoride.

It is prepared from Benzene Diazonium tetra fluoro borate.

28. List the used of Boron Tri fluoride

• It used to prepare catalyst like HBF4

• It used as a Fluorinating agent.

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29. Explain the McAfee process of preparing Aluminum Chloride

It is prepared by heating Alumina with coke and Chlorine.

30. What are the used of Aluminum chloride

• Used as catalyst in Friedel craft reaction.

• Used as catalyst to prepare Dyes and Perfumes.

• Used to prepare petrol by cracking

31. Give the preparation of Potash Alum ( Alum )

• It is prepared by Alum stone

• Alum stone is treated with sulphuric acid.

• Calculated amount of Potassium sulphate is added.

• The solution is crystallized and purified by recrystallization.

32. Give the action of heat of Potash alum

33. What is Burnt Alum

When potash alum is heated at 500K, it loses all the water molecules and swells up. This swollen mass is called as Burnt alum.

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34. Give the difference between graphite and diamond

S.

Nm Graphite Diamond 1 It is soft It is hard

2 Sp2 hybridised sp3 hybridised

3 Each carbon forms three C-C sigma bonds

Each carbon forms four C-C sigma bonds

4 It has free electrons It has no free electrons

5 Conducts electricity Do not Conducts electricity

6 Hexagonal sheet shape Tetrahedron shape

7 C-C bond length is 1.410A C-C bond length is 1.540A

9 It has weak Vander Waals force

It has strong covalent bonds

10 Used as Lubricant. Used to cut glass

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35. Explain the structure of Fullerenes

( Explain the structure of Buckminster Fullerenes )

• It has a Cage structure with C50, C60 or C70 atoms

• C60 has a soccer ball structure and called as Bucky Ball.

• It has a ring structure of 20 six member ring and 12 five member ring.

• The carbon atoms are sp2 hybridised.

• The C-C bond length is 1.440A and C=C is 1.380A

• It has an Aromatic character.

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36. Explain the structure of Graphene

• It has a single planar sheet structure

• The carbon atoms are sp2 hybridised

• It has a honey comb crystal lattice.

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37. What are the used of Carbon nano tubes

• It is stronger than steel and conducts electricity.

• Used in nano electronics

• Used as catalyst

• Used to prepare polymers

• Used to prepare medicine

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38. What is producer gas

A mixture of Nitrogen and Carbon monoxide is called as Producer gas

2 C + ( N2 + O2 ) 2 CO + N2

Air Producer Gas

39. What is water gas equilibrium

40. List the used of Carbon monoxide

• oxides

• Used to prepare Producer gas ( CO + N2 )

• Used to prepare Water gas ( CO + H2 )

• It acts as a ligand.

41. Give the action of heat of Carbon di oxide.

42. Explain the reducing property of carbon di oxide

43. List the used of Carbon-di-oxide

• Used a Inert atmosphere in chemical reactions

• Used in Photosynthesis

• Used in fire extinguisher

• Used to prepare carbonated beverages. 44. List the used of Silicon tetra chloride ( SiCl4 )

• Used to prepare Semi conductors

• Used to prepare Silica gel and ceramic materials

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45. Give the industrial preparation of Carbon di oxide It is prepared by burning coke with air 2 CO + O2 2 CO2

46. Explain the Oxo process ( Ethylene to Propanal )

When ethylene reacts with CO and H2 it gives Propanal

CO + H2 + CH2=CH2 CH3-CH2-CHO

Ethylene Propanal

47. List the used of Potash alum

• Used in Purification of Water

• Used in Dyeing, paper and leather industries

• Used to arrest bleeding

• Used for water proofing textiles

48. Explain the Acidic behavior of Carbon di oxide.

49. Why the Boron have unusual Covalent bonding

• Smaller in size

• High Ionisation energy

• Similarity in electro negativity with carbon and hydrogen

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50. What are Silicones? Give the preparation and explain the different types of Silicones

Silicones are Organo Silicon Polymers with a general formula ( R2SiO )

2RCl + Si Cu/573K

R2SiCl2 � �R R | | Cl – Si – Cl + 2 H2O HO – Si – OH + 2 HCl | | R R

R R R | | | HO –Si – OH + HO – Si – OH + HO – Si – OH | | | R R R

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| | | 2 H2O + HO –Si – O – Si – O – Si – OH | | | R R R

Types of Silicones

a) Linear silicones. These are prepared by the hydrolysis of R3SiCl. They are two types i) Silicone rubber. These silicones have bridge methylene groups ii) Silicone resins. These Silicones are bonded to organic resins.

b) Cyclic Silicones These are prepared by the hydrolysis of R2SiCl2.

c)Cross linked Polymers These are prepared by the hydrolysis of RSiCl3.

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R R

| | R– Si –O –Si – R | | O O | | R– Si – O –Si – R | | R R

51. List the properties of Silicones

• They are water repellent

• They are thermal insulators

• They are electrical insulators

• They are inert.

• Lower silicones are oils. Higher silicones are waxes.

52. What are Silicates and explain the types of silicates

Silicates are minerals containing silicon and oxygen with [ SiO4 ]– 4 units.

a) Ortho silicates. Or Neso silicates

b) Pyro silicate or Soro silicates

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c) Cyclic Silicates or Ring silicates

d) Chain Silicates or Pyroxenes

e) Double chain silicates or Amphibiles

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f) Sheet or Phylio silicates

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Name of the

Silicate

General formula

Number of oxygen atoms

shared as

Bridging Oxygen

Example

1 Ortho silicates�

[ SiO4 ]– 4�

No

Phenacite�

2 Pyro silicate�.�

[Si2O7 ]– 6 one Thortveitite

3 Cyclic Silicates�

[ SiO3 ]n– 2n�

Two Beryl

4

Chain Silicates�

[ SiO3 ]n– 2n�

Two

Spodumene�

5 Double chain silicates�

[ Si4O11 ]n– 6n Two Asbestos

6 Sheet silicates��

[ Si2O5 ]n– 2n�

Three

Mica and Talc

7 Three dimensional

silicates

[ SiO2 ]n�

Four Quartz�

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1. Define Inert pair effect.

In P-block, the pair of S-electrons becomes chemical inert and do not take part in bonding. This is called as Inert pair effect.

2. Explain why Fluorine show -1 oxidation state ?

• Smaller in size

• High electro negativity and high electron affinity

• High electron charge density

3. Find the Oxidation states of the Halogen in the following a) OF2 ( +2 ) + 2F = 0

F= - 2/2

= -1

b) O2F2 ( +1×2 ) + 2f = 0 2x = - 2

F= -2/2

= -1

c) Cl2O3 ( -2×3 ) + 2x = 0

2x = 6

X= 6/2

= +3

d) I2O4 ( -2×4 ) + 2x = 0

2x = 8

X= 8/2

= +4

4. What are inter halogens compounds. Give examples

Each halogen reacts with another halogen to form inter halogens.

Ex. BrF3

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5. Why Fluorine is more reactive than other halogens?

• F-F bond energy is very low

• Highly electro negativity

6. Give the used of Helium

• Helium – Oxygen mixture is used to prevent Bends during deep sea diving

• Helium is used in electric arc welding of metals

• Helium is used in Low temperature science

• Helium is used in filling Balloons

7. Find the Hybridisation of Iodine in IF7 and its sturcure

• Hybridisation is sp3d3

• Shape = Pentagonal bipyramidal

8. Give the action of Chlorine with cold and hot NaOH

• With Cold NaOH it give Sodium hypo chlorite

• With Hot NaOH it give Sodium Chlorate

9. Give the Lab preparation of chlorine It is prepare by the action of HCl with Manganese dioxide.

MnO2 + 4 HCl MnCl2 + 2 H2O + Cl2

10. List the used of Sulphuric acid

• It is used to prepare Fertilizers and Nitric acid

• It is used to prepare pigments and explosives

• It is used as Drying agent 11. Show that Sulphuric acid is a good dehydrating agent

HCOOH + H2SO4 CO + H2SO4 . H2O

Formic acid

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12. Give the structure and formula for the following a) Nitric acid.

b) Dinitrogen Pentoxide

c) Phosphoric acid

d) Phosphine

P PH3 - Pyramidal shape

H H H

e) Phosphours acid

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13. List the used of Argon

• It prevent the oxidation of the hot filament and so it is used to increase the life of Bulbs

14. What is the valence shell electronic configuration of the 15th

group The General electronic configuration is ns2 np3

N P As Sb Bi

2s2 2p3 3s2 3p3

4s2 4p3

5s2 5p3

6s2 6p3

15. Explain any 2 chemical properties of Phosphine

a) Reducing property of Phosphine

b) Action of heat

16. Give the reaction between nitric and Basic oxides

17. Give the action of heat of PCl5 On heating PCl5 gives PCl3 and chlorine

PCl5� � PCl3 + Cl2�

18. Why HF is a weak acid but other acids are strong acids?

• Fluorine is highly electro negative and electron affinity

• H-F bond energy is very high. So difficult to break

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19. Explain the oxidizing property of Sulphur Dioxide

20. Find the Hybridisation of the following

21. Explain the Haber’s process of Ammonia N2 + 3 H2 High T & P 2 NH3

22. List the uses of Nitrogen

• It is used to prepare Ammonia and Nitric acid

• Liquid nitrogen is used in Biological preservation 23. Give the preparation of Ammonia from Urea

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24. Explain the reducing property of Ammonia

25. Give the commercial preparation of Nitric acid by Ostwald’s

process

26. Show that Nitric acid is a good Oxidizing agent

27. Show that Nitric acid is a good Nitrating agent

28. List the used of Nitric acid

• It is used as a Oxidising agent

• ��is used��Photography

• ��is used in�Gun powder 29. What is Phosphorescence ? Phosphorus glows in the dark due to oxidation. This is called as Phosphorescence 30. Give the preparation of Phosphine When sodium hydroxide reacts with Phosphorus it gives Phosphine

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31. Explain the allotropic forms of Phosphorous S.

Nm White Phosphorous Red Phosphorous

1 White phosphorous is converted to red phosphorous by heating at 4200C in the absence of air and light

Red phosphorous is converted to white phosphorous by boiling in a inert atmosphere and condensing the vapours in water.

2 It is poisonous It is non poisonous 3 It has a Garlic smell It has no smell 4 It glow in the dark due

to Phosphorescence No phosphorescence

5 Its ignition temperature is very low.

Its ignition temperature is very high

6 It spontaneously gets combusted.

No spontaneous combustion

7 It has a tetrahedral structure.

It has a linear polymeric Structure

8

32. List the used of Phosphorus

• It is used to prepare match boxes

• It is used to prepare alloys like Phosphorus Bronze 33. Give the action of heat of Phosphoric acid

( Prepare Phosphine from Phosphoric acid )

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34. Give the preparation of Ortho Phosphoric acid ( action of Phosphorus with nitric acid )

35. Explain Holmes signal

• Chemical used = calcium carbide and calcium phosphide

• Chemicals formed = Phosphine and Acetylene

• Phosphine and Acetylene catches fire.

• This will act as a signal for the approaching ships. 36. Give the action of PCl5 with Ethanol and carboxylic acid a) C2H5OH + PCl5 C2H5Cl + HCl + POCl3

b) CH3COOH + PCl5 CH3COCl + HCl + POCl3

37. Give the preparation of Oxygen from potassium per chlorate.

38. Give the lab preparation of Ozone. (Define Ozonised Oxygen)

• It is prepared by passing electric discharge through Oxygen at 20,000V.

• 10% of Oxygen is converted into ozone. This mixture is called as Ozonised oxygen.

• Pure ozone is separated by Fractional distillation

39. Explain the structure of Ozone

• Bend shape

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40. Prove Ozone is good oxidizing agent. Or How Ozone is estimated ( Action of Ozone with KI solution)

41. List the used of Oxygen

• Oxygen gas = welding

• Oxygen gas = survival of living organism

• Liquid oxygen = Rocket Fuel

42. Explain the reducing property of SO2 ( sulphur dioxide )

43. Explain the Bleaching action of SO2 (Sulphur Dioxide) Due to its reducing property, it bleaches wool and silk into Colourless �

�� 44. List the used of SO2 (Sulphur Dioxide)

• Used for Bleaching wool, silk and hair

• Used for Disinfecting plants in agriculture 45. Give the preparation of Bleaching powder

46. Give the preparation of Sulphuric acid by Contact process

It is prepared in 3 steps

2 SO2 + O2

V2O

5 / 450C

2 SO3

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47. Explain the oxidizing property of Sulphuric acid H2SO4 + H2S SO2 + 2H2O + S 48. Give the test for Sulphates or Sulphuric acid

• Sulphuric acid + Barium Chloride = White ppt

• Sulphuric acid + Lead Acetate = White ppt

49. Give the action of Chlorine with Turpentine ( Affinity for hydrogen )

50. Give the preparation of chlorine by the electrolysis of Brine solution

51. List the use of chlorine

• Purification of Drinking water

• Bleaching paper and cotton

• Extraction of Gold and Platinum

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52. Explain the Bleaching nature of chlorine It gives Nascent oxygen

53. Define Royal water or Aqua regia. Give its uses. 3:1 ratio of Conc. HCl and Conc. nitric acid is called as Royal water. It is used to dissolve gold

54. List the used of Hydrochloric acid

• Prepare chlorine and ammonium chloride

• Purification of bone black

• Extraction of Glue from bones

• Used to prepare Glucose from Starch.

55. Give the action of HF with Glass and silica HF acid cannot be stored in glass containers. Because it reacts with Silica and glass

56. List the properties of Inter halogens compounds

• The central atom must be large

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• Since Fluorine is smaller in size, it has high Coordination number �

• They are strong oxidising agents �

• They undergo Auto ionizations�

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57. List the used of Krypton

• Used in Flash bulbs

• Krypton lamps pass through dense fog so used in Airports 58. List the used of Radon

• Used as source for Gamma rays

• Radon capsules – destroy cancer cells 59. List the used of Xenon

• Used in Flashbulbs and Lasers

• Used in Flash bulbs by Photographers

60. List the used of Neon Used in Adds as Neon signs with brilliant red colour.

61. Why nobles gases have large Ionisaton energy They have fully filled stable np6 electronic configuration

62. Explain the Oxidising property of chlorine

63. Prove HI is strong reducing agent.

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1. What are Transition metals. Give examples Elements from group 3 to 12 are called as Transition metals. Example. Gold, Silver, Copper , Iron, Platinum 2. Explain the Oxidation states of the 3d elements

• The energy difference between the ns and the (n-1)d orbitals is very less. So they show variable oxidation state.

• At the beginning +3 is stable. Ex. Sc+3

• At the end +2 is stable. Ex. Zn+2

• Copper shows +1 and +2.

• Scandium show only +3.

• Manganese shows +2 to +7 oxidation state.

• Iron show +2 and +3 oxidation states.

• Mn+2 is more stable than Mn+3. Because Mn+2 is having half filled stable d5 electronic configuration.

3. Why Cu+2 is coloured but Zn+2 is colourless ?

• Zn+2 is having fully filled stable 3d10 electronic configuration

• Zn+2 has no single electrons to excite

• Zn+2 has no d-d transition.

• But Cu+2 have single electrons to excite. 4. What are interstitial compounds ? When atoms like hydrogen or Nitrogen are trapped in the interstitial holes of the metal lattice are called interstitial compounds. Ex TiC.

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5. Give the preparation of Potassium dichromate

Conversion of Chromite ore to Sodium Chromate

4FeO.Cr2O3 + 8Na2CO3 + 7O2 10000C

8Na2CrO4 + 2Fe2O3 + 8CO2

Conversion of Sodium Chromate to Sodium Dichromate

2Na2CrO4 + H2SO4 Na2Cr2O7 + H2O + Na2SO4

Conversion of Sodium Dichromate to Potassium Dichromate

Na2Cr2O7 + 2KCl K2Cr2O7 + 2NaCl

6. Write the electronic configuration of Ce+4 and Co+2

• Ce+4 : [Xe] 4f 0 5d0 6s0

• Co+2 : [Ne] 4s0 3d 7

7. Which is stable Fe+2 or Fe+3 ? Explain

• Fe +2 : [Ne] 4s0 3d 6

• Fe +3 : [Ne] 4s0 3d 5

• Fe +3 is more stable. It is having half filled stable 3d5 electronic configuration

8. Define Std. Electrode potential. It is the std Emf measured at 273K when 1Atm of Molecular Hydrogen is oxidised to solvated proton at the electrode.

9. Explain the variation of E0 ( Std Redn Potential) in the 3d

series

• Moving from Ti to Zn the E0 value becomes less negative.

• Manganese half filled stable 3d5 configuration so it has more negative E0 value

• Zinc fully filled stable 3d10 configuration so it has more negative E0 value

• Copper has positive E0 value

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10. Calculate the number of unpaired electrons and Magnetic moment in Ti+3 and Mn+2

Sc+2 Ti+2 Cr+2 V+2 Mn+2 Fe+2 Co+2 Ni+2 Cu+2 Zn+2 d1 d2 d3 d4 d5 d6 d7 d8 d9 d10

11. Explain the Ionization enthalpy of the 1st Transition

elements

• The IE value of the d-block elements is in between the s and the p block elements

• Moving along the period the nuclear charge increases so the IE value also increase

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12. Which is a strong reducing agent. Cr+2 or Fe+2 ?

• The Std electrode potential of Cr+2 is –0.91V but for Fe+2 it is –0.44V.

• If the E0 value is greater negative, the metal is a powerful reducing agent.

• They will readily lose a electron.

• So Cr+2 is a strong reducing agent. 13. Why Cr+3 is a reducing agent but Mn+3 is a oxidising agent

• The Std electrode potential of Cr+3 is –0.41V but for Mn+3 it is +1.51V. The E0 value of Mn+3 is larger than Cr+3.

• If the E0 value is greater negative, the metal is a powerful reducing agent.

14. Copper has positive E0 value. Give reasons

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• Elemental copper is more stable than Cu+2 ion 15. Which of the following will be coloured Conditions for colour is d0 and d10 are colourless Ti+2 V+3 Sc+2 Cu+ Sc+3 Fe+3 Ni+2 Co+3 Fe+2 Ti+4 d2 d2 d1 d10 d0 d5 d8 d6 d5 d0

Colour Colour Colour No No Colour Colour Colour Colour No

16. In the 3d series, which metal has +1 oxidation state, why?

• Copper show +1 oxidation state.

• Because by losing one electrons it becomes a stable fully filled 3d10 configurations.

17. Transition metals show high melting points. Explain why?

• They have strong inter atomic attraction

• They have many d-electrons to form strong metallic bonds.

18. Why transition metals forms alloys ?

• A mixture to two or more metals is called as a Alloy.

• They are similar in atomic size

• One metal atom can easily replace the crystal lattice of another metal atom. Ex. Gold-Copper alloy.

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19. Explain the Hume Rothery Rules for the formation of a alloy

• The difference in the atomic radius should be lesser than 15%

• The difference in the electro negativity should be zero.

• They should have same crystalline structure and valence 20. Explain the position of D-block in the periodic table

• Groups 3 to 12 are called as D-block elements There are 4 series a) 3d series ( Sc to Zn ) 4th period b) 4d series ( Y to Cd ) 5th period c) 5d series ( Hf to Hg ) 6th period d) The 7th period elements are Radio active

• Zn, Cd and Hg don’t have partially filled d-orbitals. But their properties are same as transition elements.

21. What is electronic configuration of Cr and Cu

• Cr24 = [Ar18] 4s1 3d5

• Cu29 = [Ar18] 4s1 3d10

22. Explain the variation of Atomic and ionic size of Transition

elements ( d-block ) a) Along the period, the Radius decreases.

Along the period, the electrons are added to the same orbitals and the nuclear charge increases.

b) Along the group, the Radius increase Along the group, the electrons are added to new orbitals and the nuclear charge decreases.

23. Why the atomic radius of Zinc slightly increases

• Zn has d10 configuration

• It has 10 electrons, so the repulsion between the electrons is more than the nuclear charge. So the orbital expands.

24. Why Mn+2 is more stable than Mn+4.

Mn+2 is having half filled stable 3d5 electronic configuration.

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25. List the different between diamagnetic and paramagnetic S.Nm Diamagnetic Paramagnetic 1 They have paired electrons They have unpaired electrons 2 They are repelled by the

magnetic field They are attracted by the magnetic field

3 Ex. Zinc Ex. Iron 26. What are the advantages of catalyst

• Requires low energy

• Minimum waste production

• Increase the conversion of reactant to product. 27. What is Zeigler-Natta Catalyst. Give its application Mixture of TiCl4 and Trialkyl aluminium is called as Zeigler-Natta Catalyst. It used for Polymerization reactions. n CH3–CH=CH2 TiCl

4 + Al(C

2H

5)3 – [ CH–CH2] –

Propylene

CH3 Poly Propylene

28. Give the characteristic (properties) of interstitial compounds ?

• They are hard

• They have good electrical and thermal conductivity

• They have high melting point higher than the pure metals

• The metal hydrides are good reducing agents

• The metal carbides are chemically inert.

• Ex. TiC 29. Why Transition metals ( D block ) forms complexes ?

• The metal ions are smaller in size

• They have vacant orbitals which can accept an electron pair.

• They are highly charged.

• Ex. K4[Fe(CN)6] 30. Give the action of heat of Potassium Dichromate

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31. Prove Potassium Dichromate is a good oxidizing agent

32. List the uses of Potassium Dichromate

• It is used as Oxidising agent

• It is used in Dyeing and Printing

• It is used in Tanning of Leather

• It is used in the estimation of Iron compounds 33. Explain the Chromyl Chloride test. ( How will you detect a chloride ion in Qualitative analysis ) Potassium Dichromate + Chloride salt H2

SO4 Chromyl Chloride

( Red Orange Vapours )

The vapours are passed through Lead acetate to give a yellow ppt.

34. Give the action of heat of Potassium Permanganate – KMnO4

2KMnO4 K2MnO4 + MnO2 + O2

35. Explain the Oxidising property of Potassium permanganate

36. List the uses of Potassium permanganate (KMnO4 )

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37. Calculate the Equivalent mass of KMnO4 in various

mediums

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1. What are inner transition elements Inner transition elements consist of two series

• Ce to Lu following La ( Lanthanoids ) 4f series – 14 elements

• Th to Lr following Ac ( Actinoids ) 5f series – 14 elements 2. Explain the position of Lanthanides in the Periodic table

• Lanthanides belong to group 3 and period 6

• Lanthanoids, electronic configuration is [Xe] 4f 2¯14 5d0

¯1 6s2

• The common oxidation state of Lanthanoids is +3

• The electrons enter in the 4f orbital

• All the14 elements have same physical and chemical properties

• Hence they are placed separately at the bottom of the periodic table.

3. What are Actinides give examples The 14 elements following Actinum from Th to Lr are called as Actioinds. Ex. Th, Lr, U, Pu and Pa. 4. Why Gd+3 and Lu+3 is colourless ?

• Gd+3 is having half filled stable 4f7 electronic configuration

• Lu+3 is having fully filled stable 4f14 electronic configuration 5. Why Gd+3 and Lu+3 is more stable ?


• Lu+3 is having fully filled stable 4f14 electronic configuration

6. Actinide contraction is greater in elements than lanthanide contraction. Explain

The 5f electrons have lesser shielding effect and greater nuclear charge than the 4f electrons.

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7. Explain Lanthanide contraction Definition As we move from Ce to Lu in the 4f series, the ionic radius gradually decreases. This is called as Lanthanide contraction. Causes of Lanthanide contraction

• Moving from Ce to Lu the nuclear charge increases.

• All the 14 electrons are added to the same 4f orbital

• Poor shielding effect of the 4f electrons

• Hence the attraction between the nucleus and the valance shell increases.

Consequences of Lanthanide contraction

• Moving from Ce+3 to Lu+3 the size decreases so the basic character also decreases.

• They have similar chemical properties.

• The second and the third transition series have similar properties

8. Compare lanthanides and actinides S.Nm Lanthanides Actinides

1 Electrons enter in the 4f orbitals

Electrons enter in the 5f orbitals

2 Binding energy of the 4f orbitals is high

Binding energy of the 5f orbitals is low

3 They do not form complex They form complex 4 They do not form Oxocation They form Oxocation.

Ex. UO2+2

5 They are colourless They are coloured. Ex. U+3 is red and U+5 is green

6 They show +2, +3 and +4 oxidation states

They show +3, +4, +5, +6 and +7 oxidation states

9. Out of Lu(OH)3 and La(OH)3 which is more basic. Why ?

• When the ionic radius increases, the basic character also increases.

• La+3 ion is larger than Lu+3, due to Lanthanide contraction.

• So La(OH)3 is more basic.

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10. Why Europium (II) is more stable than Cerium(II) ? Europium (II is having half filled stable 4f7 configuration. 11. Why Zirconium and Hafnium is have similar properties ?

• Because of Lanthanide contraction the change in the ionic radius is very small.

• So the 2nd and 3rd transition elements have similar properties.

12. Write the electronic configuration of Lanthanides and Actinides

1

Lanthanides

2

Actinides

13. Explain the Oxidation states of Lanthanides

• The common oxidation state is +3

• They also show +2 and +4 Oxidation states


• Lu+3 is having fully filled stable 4f14 electronic configuration

14. Explain the Oxidation states of Actinides

• The common oxidation state is +3

• They also show +2, +3,+4,+5,+6 and +7 Oxidation states

• Thorium shows +2 oxidation states.

• Pu and Np shows +7 oxidation states.

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1. Define a Double salt When two or more compounds are mixed together in a solution and evaporated, it gives a double salt. Ex. FAS or Mohr salt. FeSO4. (NH3)2SO4. 6H2O 2. Differentiate Double salt and coordination compounds

S. Nm

Double salt

Coordination compounds

1 The salt loses its identity The salt never loses its identity 2 It dissociates in simple ions It never dissociates in simple

ions 3 Ex. FAS Ex. K4[Fe(CN)6 ] 4 It contains cation and anion It consist of a complex ion 3. Define the following terms of Coordination compounds

• Coordination Entity Coordination entity is an ion containing the central metal atom, and the ligands attached to it. Ex. In K4[ Fe(CN)6 ], the coordination entity is [ Fe(CN)6 ]

¯ 4 ion.

• Central metal atom The central metal atom is present at the central position of the coordination entity and binds the ligands to itself by Coordinate bonds. It is also called as Lewis acid. In K4[ Fe(CN)6 ], the Central metal is Fe+2 ion

• Ligands The ligands are donor atoms which are directly bonded to the central metal atom. It is also called as Lewis base. In K4[ Fe(CN)6 ], the ligand is CN ¯ ions

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• Coordination sphere or Complex ion In the complex ion, the central metal atom and the ligands are enclosed in the square bracket with its net charge. This ions is called as Coordination sphere. In K4[Fe(CN)6 ], the Coordination sphere is [Fe(CN)6 ]

¯ 4 ions

• Coordination Polyhedron The 3D spacial arrangement of the ligands that are directly bonded to the central metal atom is called as Coordination Polyhedron. In K4[Fe(CN)6 ], the Coordination Polyhedron is Octahedron.

• Coordination number The number of ligands bonded to the central metal atom are called as coordination number. In K4[Fe(CN)6 ], the Coordination number is 6.

• Oxidation number If the all the ligands are removed along with its electron pair that were shared with the central metal atom, the resulting charge is called as Oxidation number. In K4[Fe(CN)6 ], the Oxidation number is +2. 4. What are the different types of complexes based on kind of

ligands ? a) Homoleptic complex.

The central metal atom is bonded only to one kind of ligands. Ex. K4[Fe(CN)6 ]

b) Heteroleptic complex. The central metal atom is bonded to more than one kind of ligands. Ex. K4[Fe(CN)3 Br3]

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5. Explain the Werner’s theory of Co-ordination compounds.

• There are two types of Valency a) Primary Valency b) Secondary Valency

S. Nm Primary Valency Secondary Valency

1 Oxidation number of the metal atom

Coordination number of the metal atom

2 Its value will be positive or Zero

It is the number of ligands bonded to the central metal ion

3 Satisfied only by negative ions

Satisfied by Positive ions, Negative ions or Neutral molecules

4 It is non-directional It is directional

• Secondary Valency is 4 = Tetrahedral shape

• Secondary Valency is 6 = Octahedral shape

• There are two spheres around the metal atom. a) The Inner sphere is called as the Coordination sphere.

The groups preset in this sphere are firmly attached to the central metal.

b) The outer sphere is called as the Ionisation sphere. The groups preset in this sphere are loosely attached to the central metal.

Limitations of Werner’s theory It fails to explain the Colour and the magnetic properties

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6. What are the limitations of Werner’ s theory It fails to explain the Colour and the magnetic properties 7. Define Structural Isomerism and explain its types. ? Complexes having same molecular formula but different connections between the ligands atoms are called as Structural isomerism. There are 4 types.

• Linkage isomerism When an Ambidentate ligand is bonded by two different donor atoms to the central metal are called as Linkage isomerism. $��%�&��'��(��)�*�� $��%�&��'��%�(�')�*�� • Coordination isomerism Coordination compounds having both the cationic and the anionic complex ion gives Coordination isomerism. The ligands are interchanged between the cationic and the anionic complex.

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• Ionisation isomerism When a simple ion acts as ligand and exchanges with one or more ligands present in the coordination sphere is called as Ionisation isomerism. They give different ions in solution. $��%�&��'��)�*�� $��%&��'��*�)��

• Solvate or Hydrate isomerism When solvent molecules like water are exchanged by the ligands in the crystal lattice of the coordination compounds is called as solvate isomerism. � � $��%&��'�)��+�,-��"��

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8. Define Ambidentate ligands

when the ligand is capable of bonding by more than one Donor

atom to the central metal ion, are called as Ambidentate ligands.

Ex. –NO2 ligand

9. Define Hybridisation Hybridisation is the intermixing of atomic orbitals of same energy to give equal number of new orbitals of same energy.

10. Define Labile and Inert complex

• Complex which undergo ligand substation very fast are called

Labile complex

• Complex which undergo ligand substation very slowly are called

Labile complex

11. Explain the Geometrical Isomerism in square complexes Complexes having different three dimensional spatial arrangements of the ligands around the central metal atom are called as Geometrical Isomerism

• When two similar groups are present on the same side it is called as Cis isomer.

• When two similar groups are present on the opposite side it is called as Trans isomer.

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Example TYPE CIS ISOMER TRANS ISOMER

MA2B2

MA2BC

MABCD

M(XY)2

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When two similar groups are present on the same side it is called as Cis isomer.

When two similar groups are present on the opposite side it is called as Trans isomer.

MA2B4

M(XX)2B2

2

When the three similar groups are present in the corners of the triangular face and the other three groups in the opposite face of the octahedron. It is called as Fac isomer

When the three similar groups are present in the meridian. It is called as Mer isomer.

MA3B3

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Enantiomers are optically active mirror images. Ex. d and l tartaric acid

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• Compounds with chiral carbon are optically active

• Enantiomers are optically active mirror images.

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• The ligand-metal bond is covalent bond. And formed by the sharing of electrons between the metal atom and the ligands.

• The ligand should contain at least one filled orbital with a lone pair of electrons.

• To accept the electron pair donated by the ligands, the central metal atom should contain vacant orbitals.

• The vacant orbital of the metal atom under goes Hybridisation. Hybridisation is the intermixing of atomic orbitals of same energy to give equal number of new orbitals of same energy.

• The vacant metal orbitals linearly overlap with the filled ligand orbitals to form metal-ligand coordinate sigma bonds.

• The hybridised orbitals are directional in space and give geometry to the complex.

• Central metal atom with unpaired electrons – Paramagnetic

Central metal atom with paired electrons – Diamagnetic

• Ligand like CO and CN¯ are strong field ligands, which causes the pairing of electrons in the metal atom.

• Greater the ligand-metal orbitals overlapping, greater is the bond strength.

• In octahedral complex,

Orbitals Type of complex formed

( n-1 )d

Low spin complex

nd High spin complex.

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17 . Show than [Fe(CN)6 ]-3 is Octahedral and Paramagnetic using Valence bond theory.

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18 . Show than [CoF6 ]-3 is Octahedral and Paramagnetic using Valence bond theory.

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• It fails to explain the colour of the complex

• It fails to explain the inner orbital and the outer orbital complexes of the same metal.

• It considers only the spin of the magnetic moment. It does not consider the other components.

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• The bonding between the central metal atom and the ligand is purely a ionic bond.

• In coordination compounds the central metal atom and the ligands are considered as Point charges for charged metal atoms. and electric dipoles for Neutral metal atom.

• In the isolated state, all the five d-orbitals are degenerate. The ligands form a spherical field of negative charge around the metal atom. Due to the repulsion between the electrons, the energy of the five d-orbitals will increase.

• The ligands approach the metal atom in the bonding direction. Due to repulsion, the energies of dx2-y2 and dz2 orbitals lying along the axis will increase. The five d-orbitals will split into two sets. This is called as Crystal field splitting.

• When the ligand approaches further, there will be an attraction between the negative charged ligand and the positive charged metal ion. The net energy decreases and leads to complex formation.

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• When the ligand approaches the metal along the axis, eg

orbitals are closer to the ligands than the t2g orbitals.

• The maintain the average energy, the energy of dx2-y2 and dz2 orbitals will increase by 3/5�0

• The energy of dxy, dxz and dyz will decrease by 2/5�0

• �0 is the crystal field splitting energy for Octahedral complexes.

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• When the ligand approaches the metal diagonally, the t2g orbitals are closer to the ligands than the eg orbitals.

• The maintain the average energy, the energy of dx2-y2 and dz2 orbitals will decrease by 3/5�t

• The energy of dxy, dxz and dyz will increase by 2/5�t �t is the crystal field splitting energy for Tetrahedral complexes

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• The crystal field splitting power of the ligands are arranged in the increasing order. this order is called as Spectro chemical series

• The ligands present on the right side of the series have large crystal field splitting. And called as strong field ligands. Ex. CN¯

• The ligands present on the left side of the series have smaller crystal field splitting. And called as weak field ligands. Ex. Br¯

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No paired electrons so Eiso = 0

a) For high spin complex

Electronic configuration = t2g3 eg 2

b) For low spin complex


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Since the CFSE value is large positive value, it forms only High spin

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a) For high spin complex


b) For low spin complex


Since the CFSE value is large negative value, it forms only Low spin

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It is the energy difference between the electronic configuration of the ligand field and the Bary center. CFSE ( �E0 ) = ( ELF ) -(EIso )

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It is the energy associated with the absorbed wavelength of light is called as Crystal field splitting energy � = h c � � = Crystal field splitting energy h = planks constant c = velocity of light � = wavelength ��

• Ti+3 is having d1 configuration.

• The single electron is present in the t2g orbital.

• When light is absorbed, the electron is excited to the higher eg orbital. It is called as d-d transition.

• Its electronic configuration changes from t2g1 eg0 to t2g0 eg1

• Its CFT energy is 239.7 KJ/mol

• The transmitted colour is purple

30. Why Cu+ and Zn+2 is colour less ?

• They have d10 configuration

• Absence of single electrons

• No d-d transition

31. Why Sc+3 and Ti+4 is colour less ?

• They have d0 configuration

• They do not have d-d transition

• Absence of single electrons

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32. [ Ti (H2O)6]+3 is coloured while [ Sc (H2O)6]+3. Is colorless.

[ Sc (H2O)6]+3 is colorless because,

• It has Vacant d0 electronic configuration

• It has no single electrons to excite.

• It do not have d-d transition

• But Ti+3 have single electrons to excite.

33. [ Ni (H2O)6]+2 is green but [ Ni (CN)4]-2. Is colorless. Why ?

• CN �- is a strong field ligand and form low spin complex. It pairs the d-electrons of nickel. There are no single electrons. And no d-d transition. � � ��

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• H2O is a Weak field ligand and form high spin complex. It does not pair up the d-electrons of nickel. There are 2 single electrons. And there will be d-d transition.

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¯ 2 is diamagnetic but [ Ni Cl4]-2 is paramagnetic.

Explain using CFT?

a) [ Ni (CN)4] -2 is diamagnetic

• CN - is a strong field ligand. It pairs the d-electrons of nickel. There are no single electrons. It form low spin complex.

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• Cl - is a Weak field ligand. It does not pair the d-electrons of nickel. There are 2 single electrons. It form high spin complex.

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35. What are metal carbonyls. Metal carbonyls are transitions metal complexes of carbon monoxide with metal-carbon bonds. Ex. [ Ni(CO)4 ]

36. Explain the classification of metal carbonyls i) Depending upon the number of metal atom

a) Mono nuclear carbonyls These compounds contain only one metal atom. Ex. [ Ni(CO)4 ]

b) Poly nuclear carbonyls These compounds contain more than one metal atom. Ex. [ Fe2(CO)9 ]

ii) Depending upon the structure

a) Non- bridge carbonyls These compounds do not contain any bridging carbonyls ligands. Ex. . [ Ni(CO)4 ]. These are divided in to two types

• Non- bridge carbonyls containing only terminal carbonyl lignads . Ex. [ Ni(CO)4 ]

• Non- bridge carbonyls containing both terminal carbonyl ligands and Metal-Metal bonds . Ex. [ Mn2(CO)10 ]

b) Bridge carbonyls These will contain bridging carbonyls ligands, terminal carbonyl ligands and Metal-Metal bonds. Ex. [ Fe2(CO)9 ]

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37. Draw the structure of the following metal carbonyls. a) [ Mn2(CO)10 ]

b) [ Fe2(CO)9 ]

c) [ Co2(CO)8 ] without bridge

d) [Co2(CO)8 ] with bridge

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38. Explain the bonding in metal carbonyls a) The carbon atom of the carbonyl ligand donates an electron

pair to the vacant d-orbital of the metal atom. And forms an M CO sigma bond.

b) This increases the electron density in the d-orbitals of the

metal atom and makes it electron rich. So the metal atom transfers the electron back to the ligand. This is called as �-back bonding

c) In metal carbonyl the electron density moves from the ligand to the metal by sigma bond and form the metal to the ligand by pi-bond.

Sigma Bond

39. What are the significance of Stability constant ?

• It the measure of the stability of the complex

• It the stability constant value increases the stability of the complex also increases.

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40. Define stability constant Stability constant of a complex is the measure of its resistance to replace one ligand by another.

41. Give the relation between stability constant and dissociation equilibrium constant

Stability constant of a complex is the measure of its resistance to replace one ligand by another.

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42. Give the relation for stepwise & overall formation constant

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43. List the applications and importance of coordination

complex

• Phthalo Blue- a blue pigment used as printing ink

• [Ni(CO)4 ] is used in the purification of Nickel in Mond’s process

• EDTA is used in the separation of Lanthanides and to remove

lead poisoning.

• In Mac Arthur Forrest cyanide process, cyanide complex is used

in the extraction of Gold and Silver

• [Ni (DMG)2 ] complex is used in the estimation of Ni+2 ions.

• Cis-Platin complex is used in the Cancer treatment.

• Chlorophyll is a green pigment containing Mg+2 ions. Helps in the

photosynthesis of plants.

• Ziegler Natta catalyst – [TiCl4] and Al(C2H5)3 is used in the

polymerization of Ethylene

• Wilkinson catalyst - [Rh Cl (PPh3)3] is used in the

hydrogenation of Alkenes

44. Give the catalytic importance of coordination compounds

• Ziegler Natta catalyst – [TiCl4] and Al(C2H5)3 is used in the

polymerization of Ethylene

• Wilkinson catalyst - [Rh Cl (PPh3)3] is used in the

hydrogenation of Alkenes

45. List the Biological importance of Coordination

compounds

• RBC is a Fe+2 – Porphyrin complex which carries oxygen from

the lungs to the tissues.

• Chlorophyll is a Mg+2 –Porphyrin complex. It is called as

Corrin ring. Helps in the photosynthesis of plants. It

converts CO2 to Carbohydrate and Oxygen

• Vitamin B-12 is a Co+1 – Porphyrin complex

• Carboxy-peptidase is a enzyme containing Zn+2 ion which

help in digestion.

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Coordination compounds

a) Medicinal impotance

• Cis-Platin complex is used in the Cancer treatment.

• Ca-EDTA is used to remove lead and radio active metals from the

body

b) Biological importance

• RBC is a Fe+2 – Porphyrin complex which carries oxygen from the

lungs to the tissues.

• Chlorophyll is a Mg+2 –Porphyrin complex. It is called as Corrin

ring. Helps in the photosynthesis of plants. It converts CO2 to

Carbohydrate and Oxygen

47. • [Co(NH3)5Cl]SO4 complex will answer the test for sulphate ion.

It give a white ppt with BaCl2 solution

• [Co(NH3)5 SO4]Cl complex will answer the test for Chloride ion.

It give a curdy white ppt with silver nitrate solution

48. Why tetrahedral complex do not form geometrical

isomerism

• The relative positions of the 4 ligands are same with respect

to each other.

• The 4 ligands are adjacent to each other.

49.

It forms Tetra ammine copper II sulphate [ Cu(NH3)4 ]SO4

A deep blue colour complex.

[ Cu(NH3)4 ]SO4 [ Cu(NH3)4 ]+2 + SO4 -2

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1. What are the general characteristic of Solids ?

• They have a definite volume and shape

• They are rigid and cannot be compressed

• They have short ionic distance

• The ions are fixed and cannot oscillate.

• They have strong cohesive force 2. Give the classification of solids.

Solids Crystalline solids Amorphous solids Ex. Glass a) Ionic crystals ( NaCl ) b) Covalent Crystals ( Diamond ) c) Molecular crystals ( Glucose ) d) Metallic crystals ( Gold ) e) Atomic solids ( Frozen Neon ) 3. Give the different between crystalline and Amorphous

solids. S. Nm

Crystalline solids Amorphous solids.

1 Definite shape Irregular shape 2 Anisotropic Isotropic 3 True solids Super cooled liquids 4 Definite heat of fusion Heat of fusion is not definite 5 Sharp melting point No sharp melting point 6 Ex. Diamond & NaCl Ex. Glass & Rubber 7 Ions are orderly arranged Randomly arranged

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4. Define Isotropy and Anisotropy a) When the physical properties are identical in all directions it

called as Isotropy. Ex. Rubber b) When the physical properties are not identical in all

directions it called as Anisotropy. Ex. NaCl crystal

5. Define ionic crystals. Give example

• Ionic crystals contains anions and cations

• The ions are held by strong electrostatic force of attraction

• Ex.NaCl crystal 6. What are the characteristic of Ionic crystals ?

• They have high melting points

• They do not conduct electricity in the solid state

• They conduct electricity in the molten state

• They are hard.

7. What are covalent solids ? Give their characteristics. In covalent solids the atoms are held by three dimensional covalent bonds. Ex. Diamond

• They are hard


• They do not conduct electricity

• They are poor thermal conductors 8. What are Molecular solids ?

• Molecular solids contains neutral molecules.

• They are held by weak Vander Waals force.

• They are soft and do not conduct electricity 9. Explain the types of molecular crystals There are 3 types a) Non-polar molecular crystals

In Non-polar molecular crystals the molecules are held by weak London forces. They have low melting points. Ex. Naphthalene

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b) Polar molecular crystals In Polar molecular crystals the molecules are held by strong Dipole-Dipole interactions. They have high melting points. Ex. Solid Carbon di oxide.

c) Hydrogen bonded Molecular crystals In hydrogen bonded molecular crystals the molecules are held by hydrogen bonds. They are soft solids. Ex. Solid Ice 10. What are Metallic solids ?

• In metallic solids the lattice points contains positive charged metal ions and a cloud of electrons.

• They are hard


• They are good conductors of heat and electricity

• They are bright luster.

• Ex. Gold 11. Define crystal lattice The regular arrangement of the ions in a crystal is called as crystal lattice. 12. Define Unit cell The basic repeating structural unit of a crystal is called as Unit cell 13. Define Coordination number of a crystal The number of nearest neighbors that is surrounding an ion in a crystal is called as Coordination number. For BCC it is 8. 14. Explain the different types of cubic system

a) Simple Cubic unit cell ( SC ) When the atoms are present at the corners of the unit cell it is called as Simple Cubic unit cell. Its coordination number is 6. Each corner is share between 8 unit cells. 8

Number of atoms per unit cell = ----- = 1 8

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15. What are the different types of Primitive unit cells

1) Cubic 2) Tetragonal 3) Ortho rhombic 4)Hexagonal 5) Mono Clinic 6) Triclinic 7) Rhombohedral

16. Define Primitive and non-primitive unit cells

a) If a unit cell contains only one lattice point it called as primitive unit cell.

b) If a unit cell contains additional lattice points it called as

non-primitive unit cell

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17. Draw the structure of NaCl crystal

18. What is Braggs equation.

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Mass of the unit cell Density of a unit cell = ------------------------------------ Volume of a unit cell 20. How will you calculate the density of a unit cell ( Derive ) Mass of the unit cell Density of a unit cell = ------------------------------------ Volume of a unit cell Mass of the unit cell = Total number of atoms × Mass of one atom

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Molar mass (M) Mass of one atom = --------------------------- Avogadro number (NA) M Mass of the one atom = ------ NA M Mass of the unit cell = n ×-------- NA Volume of the unit cell = a × a× a = a3

M Density of the unit cell = n ×------------- a3 × NA 21. Explain the 1) AAAA 2) ABABAB

c) ABCABC (Cubic close packing) d) Hexagonal Close Packing

a) AAAA close packing type

• The spheres are Linearly arranged in one direction and repeated in two dimension.

• All the spheres of different rows align vertically and horizontally.

• Each sphere has 4 neighbors.

b) ABABAB packing type

• The second row of spheres is arranged such a way that they fit in the depression of the first row.

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• The third row of spheres is arranged similar to the first row.


c) ABABAB Close packing type (Hexagonal close packing –

hcp )

• In hcp third layer of spheres are arranged directly over the first layer.

• The tetrahedral voids of the second layer is covered by the spheres of the third layer.

• Each sphere has 12 neighbours.

d) ABCABC – Cubic closing packing (ccp)

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22. Explain Simple cubic arrangement

• The AAAA type arrangement is repeated in three dimension.

• The spheres of one layer is sitting directly on the top of the previous layer. And all the layers are identical.

• All the spheres are vertically and horizontally aligned.


• The coordination number is 6

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23. Define Packing efficiency The percentage of total volume occupied by the spheres is called as Packing efficiency Total volume occupied by the spheres

Packing efficiency = -------------------------------------------------------------×100 Volume of the Unit cell

24. How will you calculate the Packing efficiency of Simple cubic Volume of the unit cell = a × a× a = a3

a Radius of a sphere = ------- 2 4�r3

Volume of a sphere = -------- 3 Sub the value of ‘r’

Sub the value of Total Volume of sphere and volume of the unit cell in the below eqn.

Total volume occupied by the spheres

Packing efficiency = ------------------------------------------------- ×100 Volume of the Unit cell

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25. How will you calculate the Packing efficiency of Body center cubic system

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26. How will you calculate the Packing efficiency cubic close packing.

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27. Define Imperfection in solids. Give its advantages. The defects in the arrangement of the particles in a crystal, affects the physical and chemical properties. They are called as Imperfection in solids.

They are 4 types. 1.Point defect 2.Line defect 3.Interfacial defect 4)Volume defect

Advantages of Imperfection in solids

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28. Give the classification of Point defects.

29. What is Stoichiometric defect ?

Stoichiometric defect will occur due to a) Missing of Anions and Cations b) Presence of a positive ion in the interstitial position. c) Ex. Schottky and Frenkel defects

30. Explain the Schottky defect.

• Schottky defects takes place due to the missing of equal number of Anion and cation from the crystal lattice.

• Example. NaCl

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• The cation and the Anion should be similar in size

• There is no change in the Stoichiometric of the crystal

• Schottky defect will decrease the density of the crystal. �

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• Frenkel defects takes place due to the dislocation of ions from the crystal lattice.

• The missing ion occupies the interstitial position.

• Example. AgBr

• The cation and the Anion should be different in size

• There is no change in the Stoichiometric of the crystal

• Frenkel defect does not decrease the density of the crystal. �

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32. Explain the metal excess defect

• When the metal ions present more than the anion. It called as Metal excess defect. Ex. NaCl

• The electrical neutrality is maintained by the presence of a extra electron in the interstitial position. Ex. NaCl Crystal

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33. Explain the metal deficiency defect.

• When the metal ions present lesser than the anion. It called as Metal deficiency defect. Ex. FeO

• Fe+2 is missing from the crystal lattice.

• To maintain electrical neutrality, two Fe+2 ion oxidises to Fe+3 ion.

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34. Why ZnO turns yellow on heating. ?

• This is due to the formation of Metal excess defect.

• On heating it loses oxygen atom and forms a free Zn+2 ion. This Zn+2 ion and electrons occupy the interstitial position.

35. What are impurity defects.

• The addition of a impurity ion to a ionic solid is called as Impurity defects.

• Ex. Addition of CdCl2 to silver chloride.

• Cd+2 ions replaces Ag+ ion in the crystal.

• To maintain electrical neutrality one of the Ag+ ion will leave the crystal lattice.

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1. Define a rate of a reaction. And give its unit. The change in the concentration of the reactant in a chemical reaction per unit time is called as Rate of a reaction. It unit is Mol L C 1 S C 1

Change in the concentration of the reactant Rate = -------------------------------------------------------- Change in time

2. Define Instantaneous rate The rate of the reaction at a particular instant during the reaction is called as Instantaneous rate 3. Define Average rate The change in concentration of reactants at a given interval of time in a chemical reaction is called as Average rate

4. Differentiate rate of a reaction and Rate constant S.

Nm Rate of a Reaction Rate Constant

1 It is the speed at which the reactants are converted into products

It is a proportionality constant

2 It is measured as the decrease in the concentration of the reactant

It is equal to the rate of the reaction, when the concentration of the reactants are unity.

3 It depends on the initial concentration of the reactant

It does not depends on the initial concentration of the reactant

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5. Define Rate law Rate law is the expression which relates the rate, the rate constant and the concentration of the reactants.

aA + bB Product

Rate = K [ A ]a [ B ]b �

6. Define Rate constant Rate constant is equal to the rate of the reaction, when the concentration of the reactants are unity.

aA + bB Product

Rate = K [ A ]a [ B ]b

When [ A ] = [ B ] = 1

Then Rate = K

7. Define Elementary reaction

Each and every single step in a reaction mechanism is called as Elementary reaction

8. Define Molecularity

Molecularity is the total number of reactants present in the elementary step.

9. Define Order of a reaction

It is the sum of the powers of the concentration terms present in the rate law.

aA + bB Product

Rate = K [ A ]a [ B ]b

Order = a + b

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10. Differentiate Order of a reaction and Molecularity S.

Nm Order of a reaction

Molecularity

1 Definition: It is the sum of the powers of the concentration terms present in the rate law.

Definition: It is the total number of reactants present in the elementary step.

2 Its value can be zero, fraction or a integer.

Its value is always a whole number and cannot be zero.

3 It assigned for the overall reaction

It assigned for each elementary step of the mechanism.

11. Define Rate determining step with an example The slowest step in a chemical reaction is called as rate determining step. The rate depends on this step. Ex. Decomposition of hydrogen peroxide in the presence of I – It takes place in two steps Step-1 H2O2 + I – Slow H2O + OI – -------- 1 step

Step-2 H2O2 + OI – H2O + O2 + I – -------- 2 Over all reaction is 2 H2O2 2 H2O + O2

Step 1 is the rate determining step, since both H2O2 and I – are present. It a bimolecular reaction.

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12. Derive the rate constant for the first order reaction

Let us consider a reaction

A product

Rate = K [A ]1

-d[A] Rate = -------- dt

Therefore

-d[A]

K[A] 1 = --------

dt

-d[A]

Kdt = -------- ----- 1

[A]

Integrating eqn 1, we get

-d[A] K �dt = �----------

[A]

K ( t-0 ) = – ln [A] – ( – ln[A0] ) ---- 2

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Kt = – ln [A] + ln [A0]

[A0] Kt = ln --------- [A]

[A0] Kt = 2.303 log --------- [A]

2.303 [A0] K = --------- log --------- t [A]

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13. Give some examples for first order reaction.

• Decomposition of Dinitrogen pentoxide

• Decomposition of Thionyl chloride

• Decomposition of Hydrogen peroxide

• Isomerism of cyclo propane to propene 14. Define Pseudo first order reaction.

By taking one the reactant concentration in excess, a second order reaction can be converted to first order reaction. Such reactions are called as Pseudo first order reaction. Ex. Acid hydrolysis of Ester. CH3COOCH3 + H2O + HCl CH3COOH + CH3OH Rate = K [ Ester ]

15. Define Zero order reaction When the rate of a reaction is independent to the concentration of the reactant over wide range of concentration is called as Zero order reaction. Ex. Decomposition of Nitrous oxide in the presence of Platinum A Product

Rate = K [ A ]0

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16. Give some examples of Zero order reactions

• Decomposition of Nitrous oxide in the presence of Platinum

• Photo chemical reaction between H2 and I2

• Iodination of Acetone in acid medium 17. Derive the integrated rate law for the Zero order reaction

Let us consider a reaction

A product

Rate = K [A ]0

-d[A] Rate = -------- dt

-d[A] K[A] 0 = -------- dt

-d[A] K (1) = -------- dt

Kdt = -d[A] ----- 1

Integrating eqn 1, we get

K �dt = � -d[A]

Kt = [A0] – [A]

[A0] – [A]

K = ---------------- t

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18. Define Half life period The time required to convert the initial reactant concentration by one half is called as Half life period.

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19. Define and Derive half life period for a first order reaction.

( Why the half life period is independent to the initial concentration )

The time required to convert the initial reactant concentration by one half is called as Half life period.

2.303 [A0] K = --------- log --------- t [A]

[A0] If [A] = ----------- and t = t½ 2 Then

2.303 [A0] K = ------------ log -------- t½ [A0] /2 2.303 t½ = ---------- log 2 K

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2.303 × 0.3010 t½ = ------------------------ K 0.6932 t½ =-------------- K

Hence the half life period is independent to

20. Derive half life period for a Zero order reaction.

[A0] – [A] K = ---------------- t

[A0] If [A] = ----------- and t = t½ 2 Then

[A0] – [A0] / 2 K = -------------------------- t½ 2 [A0] – [A0] K = ------------------ 2 × t½ [A0] – [A0] K = ------------------ 2 × t½

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2 [A0] – [A0] t½ = ------------------ 2 K [A0] t½ = ------------------ 2 K

21. Define Activation energy

The minimum energy required by the molecules to react, and form the products is called Activation energy.

22. Write the Arrhenius equation

K = Ae – Ea / RT ------- 1

K = Rate constant A = Frequency factor

Ea = Activation energy R = Gas constant T = Temperature

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23. Prove the time taken for 99.9% completion is 10 for 50%.

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24. Derive Arrhenius equation on the effect of temperature on reaction rate

Arrhenius equation gives the effect of temperature on the

reaction rate. The equation is

K = Ae – Ea / RT ------- 1

K = Rate constant A = Frequency factor

Ea = Activation energy R = Gas constant

T = Temperature

If K1 and K2 are the rate constants at T1 and T2 temperatures.

Taking ln on both sides Ea

ln K1 = ln A — ------- ------- 2 RT1

Ea

ln K2 = ln A — ------- ------- 3 RT2

Ea Ea

ln K2 – ln K1 = — -------- + --------- RT2 RT1

K2 Ea 1 1

ln ------- = ------- × ------ — ------ K1 R T1 T2

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K2 Ea T2 – T1 ln ------ = -------- × ------------- K1 R T1T2 K2 Ea T2 – T1 2.303 log ------ = -------- × ------------- K1 R T1T2 K2 Ea T2 – T1 log ------ = ----------- × ------------- K1 2.303R T1T2

25. Define a catalyst. A catalyst is substance which alters the rate of a reaction without undergoing any chemical change. 26. Define Collision Rate. The number of Collisions taking place per second per liter of the reactant.

27. Explain the Collision theory of Bimolecular reactions.

• It is based of kinetic theory of gases

• According to this theory, chemical reactions occur due to the collisions between the reacting molecules.

Ex. A2 + B2 2 AB

• Rate � number of collisions per liter per second

• Number of collisions � concentration of the reactants.

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• The minimum energy posed by the molecules to react and

form the product, is called Activation energy.

• Molecules having lesser energy than the activation energy will not react.

• Out of 1018 collisions only four collisions are converts the reactants into products.

• The collision also depends on the Orientation factor. Even if the reactant molecules collide, they will not reacts unless the orientation of the reactant molecules is suitable for the formation of the transition state.

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Fraction of effective collision is given by

Rate = p . f . Collision rate

Compare Eqn 1 and 2

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28. Explain the factors affecting the rate of a reaction

• Nature of the reactant Gas phase reactions are faster than the reactions for solid and liquid reactants. Ex sodium metal reacts faster with iodine vapour than solid iodine.

• Surface area of the reactants i) According to collision theory, when the surface area of the reactants increases, the collisions between the reactants also increase. ii) Surface area can be increased by decreasing the particle size. iii) Ex. Powdered CaCO3 reacts faster with HCl than Marble.

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• Concentration of the reactants i) When the Reactant concentration increases, the rate of the reaction also increases. ii) According to collision theory, when the reactants concentration increases, the number of collisions also increases. iv) Hence when the number of collisions between the reactants

molecules increases, the rate of the reaction also increases.

• Effect of Catalyst A catalyst is substance which alters the rate of a reaction without undergoing any chemical change. i) Catalyst will decrease the activation energy of the reaction. ii) Hence large number of molecules cross the Energy Barrier and converted into the products.

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