#### Model Question Paper Part V

11th Standard

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Chemistry

Time : 02:30:00 Hrs
Total Marks : 100

Part I

Choose the most suitable answer from the given four alternatives and write the option code with the corresponding answer.

15 x 1 = 15
1. What will be the basicity of H3BO3, which is not a protic acid?

(a)

One

(b)

Two

(c)

Three

(d)

Four

2. The energy of an electron in the 3rd orbit of hydrogen atom is -E. The energy of an electron in the first orbit will be

(a)

-3E

(b)

$\frac{-E}{3}$

(c)

$\frac{-E}{9}$

(d)

-9E

3. Match the list-I and list-II using the correct code given below the list.

 List-I List-II A. Li 1. 2,8,8,1 B. Na 2. 2,1 C. K 3. 2,8,18,18,8,1 D. Cs 4. 2,8,1
(a)
 A B C D 3 4 1 2
(b)
 A B C D 2 4 1 3
(c)
 A B C D 1 3 2 4
(d)
 A B C D 4 2 1 3
4. Water gas is

(a)

H2O(g)

(b)

CO + H2O

(c)

CO + H2

(d)

CO + N2

5. Plaster of Paris is obtained by heating gypsum to ______

(a)

293K

(b)

100 K

(c)

393 K

(d)

273K

6. Mathematical expression of Boyle's law is ____________.

(a)

P1V1 = P2V2

(b)

$\frac{P}{V}=Constant$

(c)

$\frac{V}{T}=Constant$

(d)

$\frac{P}{T}=Constant$

7. All the naturally occurring processes proceed spontaneously in a direction which leads to

(a)

decrease in entropy

(b)

increase in enthalpy

(c)

increase in free energy

(d)

decrease in free energy

8. For the reaction AB (g) ⇌ A(g) + B(g), at equilibrium, AB is 20% dissociated at a total pressure of P, The equilibrium constant KP is related to the total pressure by the expression

(a)

P = 24 KP

(b)

P = 8 KP

(c)

24 P = KP

(d)

none of these

9. At 100C the vapour pressure of a solution containing 6.5g a solute in 100g water is 732mm. If Kb = 0.52, the boiling point of this solution will be

(a)

102oC

(b)

100oC

(c)

101oC

(d)

100.52oC

10. Identify the incorrect statement with respect to hybridisation.

(a)

Hybridisation is intermixing of orbitals of nearly equal energies.

(b)

Shape of molecule depends upon type of hybridisation only.

(c)

Hybrid orbitals are identical in all aspects.

(d)

Hybrid orbitals can form $\sigma$ and $\pi$ bond

11. The IUPAC name of the compound ${ H }_{ 3 }C-\overset { \underset { | }{ { CH }_{ 3 } } }{ \underset { \overset { | }{ { CH }_{ 3 } } }{ C } } -CH=C{ \left( { CH }_{ 3 } \right) }_{ 2 }$ is

(a)

2,4,4 – Trimethylpent -2-ene

(b)

2,4,4 – Trimethylpent -3-ene

(c)

2,2,4 – Trimethylpent -3-ene

(d)

2,2,4 – Trimethylpent -2-ene

12. Which of the following compound can show resonance?

(a)

CH2 = CH - CH = CH2

(b)

CH2 = CH - CHO

(c)

CH2 = CH - NH2

(d)

All of these

13. Statement - I : n - butane and iso - butane are isomers.
Statement - II : Because they are having same molecular formula but differs only in the structural formula.

(a)

Statement -I and I! are correct and statement - I! is correct explanation of statement - I.

(b)

Statement - Iand II are correct but statement - II is not correct explanation of statement - I

(c)

Statement - I is correct but statement - II is wrong

(d)

Statement - I is wrong but statement - II is correct

14. Which one of the following is used as a metal cleaning solvent?

(a)

Isopropylidene chloride

(b)

Methylene chloride

(c)

Chloroform

(d)

Iodoform

15. Ozone depletion will cause

(a)

forest fires

(b)

eutrophication

(c)

bio magnification

(d)

global warming

16. Part II

Answer any 6 questions. Question no. 24 is compulsory.

6 x 2 = 12
17. Balance the following equations by ion electron method ${ Na }_{ 2 }{ S }_{ 2 }{ O }_{ 3 }+{ I }_{ 2 }\longrightarrow { Na }_{ 2 }{ S }_{ 4 }{ O }_{ 6 }+NaI$

18. An atom of an element contains 35 electrons and 45 neutrons. Deduce
(i) the number of protons
(ii) the electronic configuration for the element
(iii) All the four quantum numbers for the last electron

19. Write balanced chemical equation for the following processes
(a) heating calcium in oxygen
(b) heating calcium carbonate
(c) evaporating a solution of calcium hydrogen carbonate
(d) heating calcium oxide with carbon

20. State the following laws: (i) Avogadro's law
(ii) Gay-Lussac's law.

21. For the equilibrium PCI5(s) ⇌ PCl3(g) + CI2(g) at 25°C kc = 1.8 x 10-7 R = 8.314 Jk-1 mol-Calculate ΔGo for the reaction.

22. When the numerical value of the reaction quotient (Q) is greater than the equilibrium constant (K), in which direction does the reaction proceed to reach equilibrium?

23. Consider the molecules NH2-, NH3, NH4+. Arrange them in the decreasing order of bond angles and give reason for your arrangement.

24. Describe optical isomerism with suitable example.

25. Write down the possible isomers of C5H11Br and give their IUPAC and common names.

26. Part III

Answer any 6 questions. Question no. 33 is compulsory.

6 x 3 = 18
27. Calculate the oxidation number of underlined atoms $\\ { Na }_{ 2 }[\underline { F } e{ (CN) }_{ 6 }]$

28. Explain briefly the time independent schrodinger wave equation?

29. Elements a, b, c and d have the following electronic configurations:
a: 1s2, 2s2, 2p6
b: 1s2, 2s2, 2p6, 3s2, 3p1
c: 1s2, 2s2, 2p6, 3s2, 3p6
d: 1s2, 2s2, 2p1
Which elements among these will belong to the same group of periodic table.

30. What are metallic hydrides? Explain about it.

31. Write balanced chemical equation for each of the following chemical reactions.
(i) Lithium metal with nitrogen gas
(ii) heating solid sodium bicarbonate
(iii) Rubidum with oxgen gas
(iv) solid potassium hydroxide with CO2
(v) heating calcium carbonate
(vi) heating calcium with oxygen

32. What is inversion temperature? How is it related to Vander Waals constants?

33. What are state and path functions? Give two examples

34. Ethylene glycol (C2H6O2) can be at used as an antifreeze in the radiator of a car. Calculate the temperature when ice will begin to separate from a mixture with 20 mass percent of glycol in water used in the car radiator. Kf for water = 1.86 K Kg mol-1 and molar mass of ethylene glycol is 62 g mol-1.

35. Which of the following compounds will not exist as resonance hybrid? Give reason for your answer.
(i) CH3 - OH
(ii) R-CONH2
(iii) CH3-CH = CH-CH2NH2

36. Part IV

5 x 5 = 25
37. Write the steps to be followed while balancing redox equation by oxidation number method.

38. The quantum numbers of six electrons are given below. Arrange them in order of increasing energies.If any of these combination(s) has/have the same energy lists.
(i) n=4, l=2 m1 = -2,ms= - $\frac { 1 }{ 2 }$
(ii) n= 3, l= 2, m1=1,ms = +$\frac { 1 }{ 2 }$
(iii) n= 3, l= 1,m1 =0 m= +$\frac { 1 }{ 2 }$
(iv) n= 3, l= 2,m1 = -2,ms= - $\frac { 1 }{ 2 }$
(v) n= 3, l= 1,m1=-1,,ms=+ $\frac { 1 }{ 2 }$
(vi) n= 4, l= 1,m1 = 0, ms= +$\frac { 1 }{ 2 }$

39. Explain about the factors that influence the ionization enthalpy.

40. Justify the position of hydrogen in the periodic table?

41. How are peroxides and superoxides formed by alkali metals?

42. 1 mole of an ideal gas is maintained at 4.1 atm and at a certain temperature absorbs 3710J heat and expands to 2 Iitres. Calculate the entropy change in expansion process.

43. What type of bond is formed between Kand CI -? Explain the bond formation.

44. Give IUPAC names for the following compounds
1) CH3 – CH = CH – CH = CH – C ≡ C – CH3
2)
3) (CH3)3 C – C ≡ C – CH (CH3)2
4) ethyl isopropyl acetylene
5) CH ≡ C – C ≡ C – C ≡ CH

45. The simplest aromatic hydrocarbon C6H6 reactsⒷ on treatment with sodium hydroxide will (C6H5OH), Phenol, © as the product. Also Cl2 to giveⒶ which on reaction with sodium hydroxide gives Ⓑ.Ⓑ of molecular formula C6H6O. @ on treatment with ammonia will give C6H7N as @. Identify Ⓐ, Ⓑ, ©, and explain the reactions involved.

46. Differentiate the following
(i) BOD and COD
(ii) Viable and non-viable particulate pollutants