II PUC Chemistry (34)

Blue Print of Model Question Paper 5

Group Unit Title Hours Marks

Part-A

I

10x1 mark

Part B

II

8x2 mark

Part C

III

8x3 mark

Part D

IV & V

11x5 mark

Total

Group-I

Physical

1 The Solid state 8 7 ü ü ü 8

2 Solution 9 8 üü ü 7

3 Electrochemistry 9 8 ü ü ü 8

4 Chemical kinetics 9 8 ü ü ü 8

5 Surface chemistry 6 5 ü 5

Total of Group-I 41 36 36

Group-II

Inorganic

6 General principles and processes of isolation of elements

5 4 ü ü 4

7 The p-block elements 11 10 ü üüü 10

8 The d and f-block elements

9 8 ü üü 8

9 Coordination compounds 7 6 üü 6

Total of Group-II 32 28 28

Group-III

Organic

10 Haloalkanes and haloarenes

7 6 ü ü 6

11 Alcohols, phenols and ethers

8 7 ü ü 7

12 Aldehydes, ketones and carboxylic acids

9 8 ü ü ü 8

13 Amines 6 5 ü 5

Time : 3 Hrs. 15min.

14 Biomolecules 7 6 ü ü 6

15 Polymers 5 5 ü 5

16 Chemistry in everyday life

5 4 üü 4

Total of Group-III 47 41 41

TOTAL 120 105 11 14 24 30 105

SECOND PUC MODEL QUESTION PAPER -5

Time 3.15 Hr Marks-70

Instructions:

1. The question paper has four parts: A, B, C and D. All the parts are compulsory

2. Write balanced chemical equations and draw labelled diagram wherever required.

3. Use log tables and simple calculators if necessary

(Use of scientific calculators is not allowed)

PART- A

I. Answer all the questions (Each questions carries 1 mark) 10 x1 = 10

1. How many particles are present in a unit cell of fcc?

2. What happens to the vapour pressure of the liquid when temperature is increased?

3. Write the mathematical expression of Henry’s law.

4. State Faraday’s first law of electrolysis.

5. Give an example for a ter molecular reaction.

6. Name the method used for purification of silicon.

7. Identify the product A in the following reaction

XeF6 + 2 H2O → A + 4HF

8. What are enantiomers?

9. Among methanoicacid, ethanoicacid and propanoicacid which one is most acidic?

10. Which vitamin deficiency causes the disease scurvy?

PART- B

II. Answer any FIVE of the following. (Each questions carries 2 marks) 5 x 2 = 10

11. What are ferromagnetic substances? Give an example.

12. Draw a schematic diagram of H2- O2 fuel cell.

13. Define activation energy. What is the effect of a catalyst on the activation energy of a reaction

14. What are lanthanoids? Write the most common oxidation state of lanthanoids.

15. What is Williamson’s ether synthesis? Give an example.

16. How do you convert ethanoic acid into 2-chloro ethanoic acid? Name the reaction.

17. Name the class of the drugs to which the following belong?

i) Dettol ii) Brompheniramine ( Dimetapp)

18. Give an example for each of the following

a) Artificial sweetening agents b) Detergents.

Part – C

III. Answer any FIVE of the following (Each question carries 3 marks) 5 x 3 = 15

19. Write the chemical equations involved in the extraction of blister copper

from copper matte. 3

20. Decribe the manufacture of ammonia by Haber’s process. 3

21. a) Explain the oxidizing property of ozone with lead sulphide. 2

b) Write the structure of pyrosulphuric acid 1

22. Complete the following equations 3

I .S8 + 4 Cl2

II. NH3 + HCl

III. Br2 + 5 F2 (excess)

23. a) Give reason: Solution containing Cu2+ ion is coloured whereas Cu+ is colourless. 2

b) Name the 3d element which contains highest number of unpaired electrons in the ground state. 1

24. Explain the preparation of potassium permanganate from manganous dioxide. 3

25. With the help of VBT, explain the hybridisation, geometry and magnetic property of [Ni(CN)4]2-

3

26. a) Write the energy level diagram for the crystal field splitting in octahedral complexes. 2

b) Write the IUPAC name of [Cr (H2O)6]Cl3 1

Part –D

IV. Answer any THREE of the following (Each question carries 5 marks) 3 x 5 = 15

27. a)Calculate the packing efficiency in bcc crystal.

b) An element having atomic mass 60 has fcc lattice, the edge length of the unit cell

400 pm. Calculate the density of the crystal (NA= 6.022 x 1023) (3 + 2)

28. a) A 5.50 g sample of a non-volatile solute is dissolved in 250 g of benzene the

freezing point of this solution is 1.020C below that of pure benzene. Calculate the

molar mass of the solute (Kf for benzene = 5.120C/mol)

b) State Raoult’s law. Write its mathematical expression (3 + 2)

29.a) Calculate the emf of the cell Zn(s)│ Zn2+ (0.2M)║Cu2+(0.1M)│ Cu(s).

Given E0Zn = -0.76 V and E0

Cu = +0.34 V at 250C

b) Define molar conductivity. How is it related to conductivity of the solution? (3 + 2)

30 a) Derive integrated rate equation for the rate constant of zero order reaction.

b) The rate constant of a first order reaction is 1.2 x10-3 s-1. Calculate half-life period of the reaction. (3+2 )

31. a) Write any two differences between physisorption and chemisorption?

b) What is coagulation of colloids? Mention one method of coagulation of lyophobic sols.

c) Give an example for shape selective catalyst. (2 + 2+ 1)

V. Answer any FOUR of the following (Each question carries 5 marks) 4x 5 = 20

32. a) i)Explain dehydrohalogenation of alkyl halides with an example. 2

ii) Write the name of the following reaction

R-X + NaI →R-I + NaX where X = Cl, Br 1

b) Mention two reasons to show haloarenes are less reactive towards nucleophilic substitution reactions. 2

33. a) Write the mechanism of dehydration of ethanol to ethene? 3

b) Name the conjugated diketone formed, when phenol is treated with

chromic acid? Write the chemical equation. 2

34. a) How is benzaldehyde prepared by Rosenmund’s reduction? 2

b) What happens when propanone is heated with sodium hypoiodite?

Write the chemical equation. 2

c) Name the product produced when ethanal is treated with dilute alkali

followed by heating. 1

35. a) Explain the preparation of primary amines by Gabriel phthalimide synthesis. 3

b) Explain Sandmeyers reaction with an example. 2

36. a Give the reaction to show that

i) Glucose contains 5- OH groups

ii) Glucose contains a carbonyl group 2

b) What are hormones? Mention the function of thyroxin. 2

c) Name the nitrogeneous base present only in RNA. 1

37. a) Explain addition polymerisation with an example. 2

b) What are biodegradable polymers? Give an example 2

c) Give an example for synthetic rubber. 1

Scheme of valuation for model question paper for model question paper -5

Note : Any other correct alternate answer can be honoured wherever applicable

Q.No

Value points Marks

I PART- A

1 4 or four 1

2 Increases 1

3 p = KH x 1

4 The mass of the substance liberated or deposited on an electrode is directly proportional to the quantity of electricity supplied. or any other suitable definition

1

5 2 NO + O2 → 2NO2 or any other suitable example 1

6 Zone refining 1

7 XeO2F2 1

8 The optical isomers of a compound which are non- superimposable mirror images of each other.

1

9 Methanoic acid 1

10 Vitamin C 1

II PART- B

11 The substances which are strongly attracted by the magnetic field

Ex. Fe Co, Ni etc.

1

1

12

2

O2 H2

Anode – Cathode +

H2O

Aqueous electrolyte

13 The minimum extra energy that the normal reactant molecule has to acquire in order to attain threshold energy. or Energy required to form the activated complex

Ea decreases

1

1

14 The 14 elements following lanthanum.

or The elements in which the differentiating electron enters the 4f orbitals

+ 3

1

1

15 When bromoethane is treated with sodium ethoxide, ethoxy ethane is obtained

or general statement

C2H5Br + C2H5ONa → C2H5 –O – C2H5 + 2NaBr

OR

Self-explanatory equation

1

1

2

16 When ethanoic acid is treated with chlorine in presence of red phosphorus,

2-chloro ethanoic acid is obtained

CH3COOH + Cl2 ClCH2COOH + HCl

OR

Self-explanatory equation

1

1

2

17 I. Antiseptic

II. Antihistamine

1

1

18 a) Saccharin or Aspartame or any other suitable example

b) sodium laurylsulphate or sodium dodecylbenzenesulphonate or any other suitable example

1

1

Red P

III PART- C

19 2FeS +3O2→ 2FeO + 2SO2

FeO + SiO2→ FeSiO3

2Cu2S + 3O2→ 2 Cu2O + 2SO2

2Cu2O + Cu2S →6Cu +SO2

1

1

1

20

N2 + 3H2 2 NH3

Conditions: T = 700K P= 200atm catalyst = Iron oxide with small amount of K2O & Al2O3

1

1

1

21 a) Ozone oxidises lead sulphide to lead sulpahate

PbS + 4O3→ PbSO4 + 4 O2

1 1

b) O O

║║

O = S –- O —S =O

l l

OH OH

1

22 i S8 + 4 Cl2 4 S2Cl2

ii. NH3 + HCl NH4Cl

iii. Br2 + 5 F2 (excess) 2 Br F5

1

1

1

23 a) Cu2+ ion has d9 configuration, it contains one unpaired electron and d-d

transition takes place.

Cu+ has d10 configuration and has no unpaired electrons, so

d-d transition does not take place

b) Chromium

1

1

1

24. a) KmnO4 is prepared by the fusion of MnO2 with KOH and an oxidising agent

like KNO3followed by acidification.

2MnO2 + 4KOH + O2 → 2 K2MnO4 + 2 H2O

3 MnO42— + 4 H+ → 2 MnO4

-- + MnO2 + 2 H2O

1

1

1

25.

Since it has dsp2 Hybridisation the geometry is Square planar

Since it does not contain any unpaired electron it is diamagnetic in nature

1

1

1

26 a)

b) hexaaquachromium(III) chloride

2

1

Packing efficiency in Body-centred cubic structure:

27 In the triangle EFD

Face diagonal, 2 2 2 2b a a 2a= + =

∴ b 2 a= ⋅

Now in the triangle AFD

Body diagonal 2 2 2c b a= +

2 2 2c 2a a= +

2 2c 3a=

∴c = 3 a⋅

Length of body diagonal c = 4r

3 a 4r⋅ =

∴r=3 a

4⋅

Packing efficiency = Volume occupied by 2 speres in the unit cell 100

Total volume of the unit cell×

3

3

42 r3 100a

× π= ×

=

3

3

4 22 32 a3 7 4

100%a

× × × ×

×

3

3

4 22 3 32 a3 7 64 100%

a

/

/

⋅× × × × /

= ×/

= 68%

b)

1

1

1

( )=

=

=

3

31 3

A

3

0 2

 4 X 60 6.227 g / cm

400 x10 x 6.022 x 10

                                                                                      

zMda N

    

1

1

28 a)

× ×

× ×

=∆ ×

= =×

f B

f A

5.12 5.5

K w

1000 110.43 g / mol1.02

1000d

T w

d250

b) Partial vapour pressure of each volatile component in the solution is directly

proportional to its mole fraction.

p1 α x1 or 1 101p x p=

1

1+1

1

1

29

a) E0cell = E0

Cu – E0Zn

= 0.34 –(-0.76)

= 1.1 V

1

1

( )

+

+= −

=

=

=

=

−

20

cell cell 2

cell

0.0591 [Zn ]E E log2 [Cu ]

0.0591 0.2E 1.1 log2 0.1

  1.1 – 0.0295 log 2

1.1 – 0.0295 x 0.3010    1.09 V   

b) The conductivity of all the ions present in solution containing

one mole of the electrolyte.

Relation: λm = K/c

1

1

1

30 a)

= − 0

R Rk

t

1

1

b) =

=−

12

12

0.693tk

 0.693t  

31.2 x10

= 577.5 s

1

1

1

31 a)

Physical adsorption Chemical adsorption

It involves weak vander Waal’s force It involves strong chemical bond

It is not specific in nature It is specific in nature

It is reversible It is irreversible

Enthalpy of adsorption is low The enthalpy of adsorption is high

Multimolecular layer of adsorption Monomolecular layer of adsorption

Activation energy is low Activation energy is High

Etc ….. Any two differences

b) The process of settling of colloidal particles is called coagulation

Addition of electrolyte or electrophoresis or any other suitable method

c) ZSM-5 or any other suitable example

2

1

1

1

32 a) i) When bromoethane is heated with alcoholic potash ethene is formed

or general statement

1

C2H5Br + alc KOH → C2H4 + KBr + H2O

or any other suitable example

ii) Finkelstein reaction

b) - Halogen is bonded to sp2hybridised carbon

- Due to resonance

- Partial C- X double bond character etc

( any two )

1

1

2

33

a)

Mechanism of dehydration of ethanol: It involves the following steps. Setp1: Protonation of alcohol

Step2: Formation of carbocation

Step3: Elimination of proton

H2C CH2H C C

EtheneH+

H

H H

H

b) Benzoquinone is formed

Equation

1

1

1

1

1

34

a) When benzoyl chloride is heated with hydrogen in presence of deactivated

palladium catalyst benzaldehyde is formed

1

Pd/ BaSO4

C6H5COCl + H2 C6H5CHO + HCl

b) Iodoform and sodium acetate are formed or iodoform is formed

NaOI

CH3COCH3 CH3COONa + CHI3

c) Crotonaldehyde or But-2-enal

1

1

1

1

35. a)

b) When benzene diazonium chloride is heated with cuprous chloride in con HCl

1

1

1

chlorobenzene is formed

Cu2Cl2/ con HCl

C6H5 N2CCl C6H5Cl + N2

or any other suitable answer

1

1

36. a) i) When glucose reacts with acetyl chloride or acetic anhydride penta- acetyl

glucose is formed

ii) When glucose reacts with hydroxyl amine forms oxime is formed

b) Biochemical messenger are called Hormones

or

Chemical substances secreted by ductless (endocrine glands )

Growth and development

c) Uracil

1

1

1

1

1

37. a) The process of repeated addition of monomer molecules to form a polymer

n(CH2= CH2) -(CH2—CH2-)n

or any other suitable example

b) The poymer which undergoes decomposition by biological means is called

biodegradable polymer

Ex: PHBV Or any other suitable example

1

1

1

1

c) BuNa-S or Neoprene , any other suitable Example

1