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1. When one mole of an ideal gas is compressed to half its initial volume and

simultaneously heated to twice its initial temperature, the change in entropy

is.

a. CV In 2 b. CP In 2 c. R In 2 d. (CV R) In 2

2. What are signs of the entropy change (+ or

) in the following:I. A liquid crystallises into a solid

II. Temperature of a crystalline solid is raised from 0 K to 115 K

III. 2NaHCO3 (s) Na2CO3(s) + CO2(g) + H2O(g)

IV. H2(g) 2H(g)

I II III IV I II III IV

a. - + + + b. - - - +

c. + + + - d. + - - -

3. For the reaction

Ag2CO3(s) 2Ag+ (aq) + CO3

2-(aq)

= + 6.3 kJ. Hence thermodynamic equilibrium constant at 25 C is

a. 3.2 x 10-26 b. 63.3 x 103 c. 8.06 x 10-12 d. 1.2 x 10-12

4. For a particular reaction = - 38.3 kJ and = - 113 JK-1. This reaction is:

a. Spontaneous at all temperatures

b. Non- spontaneous at all temperatures

c. Spontaneous at a temperatures below 338 K

d. Spontaneous at a temperatures above 339 K5. The standard heat of combustion of propane is 2220.1kJ mol-1. The standard

heat of vaporisation of liquid water is 44.0kJ mol-1. What is of

C3H8(g) + 502(g) 3CO2(g) + 4H2O(g)?

a. 2220.1 kJ b. 2044.1 kJ c. 2396.1 kJ d. 2176.1 kJ

6. The gas absorbs 100 J heat and is simultaneously compressed by a constant

external pressure of 1.50atm from 8 L to 2 L in volume. Hence, will be

a. 812 J b. 812 J c. 1011 J d. 911 J

7. H2S(g) HS(g) +H(g), = x1

[H2S(g)] = x2, [H(g)] = x3hence, (HS) is

a. x1 + x2 x3 b. x3 x1 x2 c. x1 x2 x3 d. x3 x1 + x2

8. H2(g) + O2 (g) H2O(l)

BE (H H) = x1 ; BE (O = O) = x2; BE (O H)= x3

Latent heat of vaporisation of water liquid into water vapour = x4 then (heat of

formation of liquid water) is:

a. x1 + x2/2 x3 + x4 b. 2x3 x1 x2/2 x4 c. x1 + x2/2 2x3 x4

e. x1 + x2/2 2 x3 + x4

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9. Given, Na(s) Na(g)

Na(g) Na+(g) + e-

Cl2(g) 2Cl(g)

Cl(g) + e-

Cl-

(g)

Na+(g)+Cl- (g) NaCl(s)

[letters above arrow ( are energy parameters], of NaCl is.

a. S + I +D E U

b. S + I + D/2 + E + U

c. S + I + D/2 E U

d. S + I + D/2 E + U

10. of CH4, C2H6 and C3H8are 210, 368.4 and 526.3 kcal mol-1. Hence,

of C4H10 is approximately:

a. 684.0 kcal b. 368.4 kcal c. 842.0 kcal d. 600.0 kcal

11. Which of the reaction defines

a. C(diamond) + O2(g) CO2(g)

b. H2(g) + F2(g) HF(g)

c. N2(g) + 3H2(g) 2NH3(g)

d. CO(g) + O2(g) CO2(g)

12. Autoionisattion of liquid NH3 is

2NH3 NH4+ + NH2

-

with = [NH4+

13. pH of the solution containing 50.0 mL of 0.3M HCl and 50 mL of 0.4 M NH3 is

[pKa(NH4+) = 9.26]

a. 4.78 b. 9.26 c. 8.78 d. 4.63

14. To prepare a buffer of pH 8.26, amount of (NH4)2 SO4 to be added into 500 mL of

0.01 MNH4OH solution [pKa(NH4+) = 9.26]

a. 0.05 mole b. 0.025 mole c. 0.10 mole d. 0.005 mole

15. If the equilibrium constant of the reaction of weak acid HA with strong base is

109, then pH of 0.1 M NaA is

a. 5 b. 9 c. 7 d. 816. Ksp of CaSO4 is 4 x 10

-12. CaSO4 is precipitated on mixing equal volumes of the

following solution :

a. 3 x 10-6 M CaCl2 and 3 x 10-6 M (NH4)2 SO4

b. 4 x 10-6 M CaCl2 and 3 x 10-6 M (NH4)2 SO4

c. 6 x 10-6 M CaCl2 and 3 x 10-6 M (NH4)2 SO4

d. In all cases

17. Some chemists at ISRO wished to prepare a saturated solution of a silver

compound and they wanted it to have the highest concentration of silver ion

possible. Which of the following compounds would they use?Ksp(AgCl) = 1.8 x 10-10,Ksp (AgBr) = 5.0 x 10

-13,

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Ksp(Ag2CrO4) = 2.4 x 10-12

a. AgCl b. AgBr c. Ag2CrO4 d. Any of these

18. pKb of CH3COO- ion is 9.26. pH of solution when 0.01 M CH3 COOH is

neutralised 50 % and at equivalence point using 0.01 M NaOH are respectively:

a. 4.63, 8.22 b. 4.74, 8.22 c. 2.37, 4.11 d. 474, 8.3719. Which of the following molecules have all the bonds equal in length?

1.PCl5 2. SF4 3. SiF4 4. NCl3

a. 1 & 2 b. 1, 2 & 3 c. 3 & 4 d. 2 ,3 & 4

20. Match the compounds with shape on the right

Column I Column II

x. XeO2F2 p. Seesaw

y. I3- q. Square Pyramid

z. BrF5 r. Trigonal Pyramidt. SO3

2- s. Linear

x y z t x y z t

a. p q r s b. p s q r

c. r s p q d. q p s r

21. The hybridization of each carbon in the molecule in the order marked is

a. All sp2 b. 1 ,2 ,3 ,4 sp2, 5, 6 sp3

b. 1, 3 ,sp2 2 ,4, 5, 6- sp3 d. 1, 2 ,3sp2 4, 5 ,6 sp3

22. The molecule that may be destabilized by adding an electron is

a. Nitrogen b. H2+

c. CN d. C223. The correct order of melting points of CaCl2, SrCl2 and BaCl2 can be given as

a. Cacl2 < BaCl2 < SrCl2 b. CaCl2 < SrCl2 < BaCl2

b. CaCl2 < SrCl2 BaCl2 d. BaCl2 < SrCl2 < CaCl2