1. What is the [HCOO– ] in the solution that contains 0.015 M HCOOH and 0.02 M HCl.

KaHCOOH = 1.8 10–4

1) 1.8 10–4 2) 1.35 10–4 3) 1.8 10–2 4) 8 10–3

2. What volume must 1L of 0.5 M CH3COOH solution should be diluted with in order to double pH? Ka = 1.810–5?1) 3.36 104 L 2) 2.76 103 L 3) 3.10 103 L 4) 1.05 104 L

3. CN – + HAc HCN + Ac– which of the following is correct equilibrium constant for the reaction?

(Given Ka(HCN) = 4.9 10–10, Ka(CH3COOH) = 1.8 10–5)1) 6.326 10–7 2) 7.84 10–15 3) 3.674 104 4) 5.16 103

4. How many moles of HCl must be removed from 1 litre of aqueous HCl solution to change its pH from2 to 3

1) 1 2) 0.02 3) 0.009 4) 0.003

5. pH of 0.1 M BOH (a weak base) is found to be 12. The solution at temperature TK will display anosmatic pressure equal to1) 0.01 RT 2) 0.10 RT 3) 0.11 RT 4) 1.1 RT

6. Four species are listed below :

I) 3HCO II) 3H O III) 4HSO IV) 3HSO F

Which one of the following is correct sequence of their acid strength1) II < III < I < IV 2) I < III < II < IV 3) III < I < IV < II 4) IV < II < III < I

7. The dissociation of water at 250C is 1.9 ´ 10–7 percent and the density of water is 1.0 g/cm3. Theionisation constant of water is :

1) 3.42 10–6 2) 3.42 10–8 3) 1.00 10–14 4) 2.00 10–16

8. .Approximate pH of 0.10 M aqueous H2S solution having K

1 and K

2 for H

2S at 250C 10-7 and 10-13

respectively is1) 4 2) 5 3) 9 4) 8

9. pKa value of CH3COOH is 4.78. Which of the following statement is correct

1) pH of 0.1 M CH3COOH is 4.78

2) pH = 4.78 then degree of dissociation of CH3COOH is maximum

3) pH = 4.78 then degree of dissociation of CH3COOH is minimum

4) pH = 4.78 then 50% CH3COOH is dissociation

10. The self ionization constant for pure formic acid, 2K HCOOH HCOO has been estimated s

10-6 at room temperature. The density of formic acid is 1.22 g/cm3. The percentage of formic acidmolecules in pure formic acid converted to formate ion is1) 0.002% 2) 0.004% 3) 0.006% 4) 0.008%

11. At what molar concentrations of HCl will its aqueous solution have an [H+] to which equal contribu-

tion come from HCl and H2O at 900C [K

w of H

2O = 10–12 M2 at 900C]

1) 850 10 2) 740 10 M 3) 750 10 4) 730 10

12. 100 ml of 0.5 M hydrazoic acid (N3H K

a = 3.6 10–4) and 400 ml of 0.1 M cyanic acid

(HOCN, Ka = 8 10–4) are mixed. Which of the following is true for final solution?

1) [H+] = 2 10–2 M 2) [N3–] = 3.6 10–2 M

3) [OCN–] = 4.571 10–3 M 4) [OCN–] = 6.4 10–3 M

13. Adding a few drops of hydrochloric acid to a beaker containing water results in the formation of hydratedspecies. Identify which hydrated species can exist in solution

I) H3O+ II) 3 2H O III) 5 2H O IV) H

2ClO–

1) I only 2) I and II 3) I, II and III 4) I, II, III and IV

14. Which of the following combinations of weak-acid dissociation constants and molar concentrationswould correspond to the SMALLEST percent dissociation?

1) Ka = 1.7 x 10-4 , Co

HA = 0.001 M 2) K

a = 1.8 x 10-5 , Co

HA = 0.01 M

3) Ka = 6.5 x 10-5 , Co

HA = 0.1 M 4) K

a = 6.5 x 10-5 , Co

HA = 0.01 MS

15. Liquid ammonia ionizes to a slight extent. At –500C, its ionic product is 10–30. The number of

anions present per mm3 of pure liquid ammonia is

1) 6 102 2) 17 10–15 3) 6 1023 4) 6 105

16. The self Ionisation equilibrium of pure formic acid 2HCOOH HCOOH2+ + HCOO– has Ionisation

product K = 10–6 mol2/lit2 at 298 K. If percentage Ionisation is 4 10–3. The density of acid in gm/ml is

1) 1.15 2) 1.725 3) 2.3 4) 2.875

17. Consider the following reactions of X

I : [Al(OH)3(H

2O)

3] + OH – [Al(OH)

4(H

2O)

2] – + H

2O

II : [Al(OH)3(H

2O)

3] + H

3O+ [Al(OH)

2(H

2O)

4]+ + H

2O

Select correct statement:1) X is an acid in I and base in II 2) X is a base in I and acid in II3) X is a base in I and II both 4) X is an acid in I and II both

18. The position of equilibrium lies to the right in each of the following reaction

2 5 3 4 2 4N H NH NH N H

3 4NH HBr NH Br

2 4 2 5N H HBr N H Br

Select the correct order of acidic strength

1) 2 5 4HBr N H NH 2) 2 4 3HBr N H NH

3) 4 2 5HBr NH N H 4) 3 2 4HBr NH N H

19. In order to prepare a buffer of pH 8.26, the amount of (NH4)

2SO

4 required to be mixed with 1 L of 0.1

MNH3 i s [pK

b = 4.74]

1) 1.0 mol 2) 10.0 mol 3) 0.50 mol 4) 5 mol

20. Find the pH (initial pH – final pH) when 100 ml 0.01 M HCl is added in a solution containing 0.1 m

moles of NaHCO3 solution of negligible volume 7 11

2 31 210 , 10 :a ak k for H CO

a) 6 + 2 log 3 b) 6 – log 3 c) 6 + 2log 2 d) 6 – 2 log 3

21. A buffer solution containing 0.04 m Na2HPO

4 and 0.02 m Na

3PO

4 is prepared. The electrolytic oxidation of

1 millimole of the oraganic compound RNHOH is carried out in 100 ml of the buffer. The reaction is :

RNHOH+H2O RNO

2+4H++4e– given that for

H3PO

4pK

a1, pK

a2 and pK

a3 are 4, 8 and 12 respectively; the dip in pH after electrolytic oxidation will be :

1) 11.7 2) 8.3 3) 3.4 4) 1

22. How many moles of HCl will be required to prepare one litre of buffer solution

(containg NaCN + HCN) of pH 8.5 using 0.01 gm formula weight of NaCN. pKaHCN

= 9.5

1) 9 10–2 2) 9 10–3 3) 7 10–2 4) 7 10–3

23. Calculate the ratio of pH of a solution containing 1 mole of CH3COONa + 1 mole of HCl per litre and

of the other solution containing 1 mole of CH3COONa + 1 mole CH

3COOH per litre

1) 1/6 2) 1/4 3) 1/8 4) 1/2

24. 20 ml.of 0.2 M NaOH are added to 50 ml of 0.2 M acetic acid. pKa = 4.74. Then pH of the solutionis1) 4.74 2) 4.56 3) 4.92 4) 5.10

25. One litre of buffer solution of pH = 6.7 can be prepared by 0.005 mole Na H2PO

4 and X mole of Na

2H

PO4. K

2 for H

3PO

4 = 610-8. The value of ‘X’ is

1) 0.1 2) 0.01 3) 0.001 4) 0.0001

26. A buffer solution of pH = 6.7 can be prepared by employing solution of NaH2PO

4 and Na

2HPO

4. If

0.005 mol of NaH2PO

4 is weighed out. The no.of moles of Na

2HPO

4 must be used to make 1 litre of

the solution is K2 for H

3PO

4 = 6 10–8

1) 0.0015 2) 0.003 3) 0.0045 4) 0.006

27. pH of a mixture which is 0.1M in CH3COOH and 0.05 M in (CH

3COO)

2 Ba is [PK

a of CH

3COOH =

4.74].1) 4.74 2) 5.04 3) 4.44 4) 7.00

28. The pH of 0.2 M NaHCO3 solution at 250C is 9.2. A 22 mL 2.0 M solution of H

2CO

3 when treated

with 80 mL 0.5 M NaOH results into formation of H2CO

3 +NaHCO

3 buffer with pH of 8.6. Hence

pKa2

of H2CO

3 is

1) 10.8 2) 7.6 3) 9.2 4) 8.6

29. H2CO

3 is diprotic acid for which Ka

1 = 4.2 10–7 and Ka

2 = 4.7 10–11. Which solution will

produce a pH close to 9?

1) 0.1 M H2CO

32) 0.1 M Na

2CO

3

3) 0.1 M NaHCO3

4) 0.1 M Na2CO

3 and 0.1 M NaHCO

3

30. Equilibrium constant of the reaction of NH4OH with strong acid is 109. Initially a solution of 0.05 M

(NH4)2 SO

4 and 0.1 M NH

4NO

3 is prepared. If 0.1 M NaOH is added in equal volumes. The pH of

solution1) 8 2) 9 3) 6 4) 10

31. What is the pH of an aqueous solution of 0.1 M ammonium formate assuming complete dissociate. pKa

of formic acid = 3.8 and pKb of ammonia = 4.8

1) 6.5 2) 7.5 3) 8.5 4) 9.5

32. The dissociation constants for aniline, propanoic acid and water are 9 10–10, 4 10–6 and 10–14

respectively. The degree of hydrolysis of 0.1 N aniline propanoate solution is1) 16% 2) 32% 3) 47.2% 4) 62.5%

33. The pH curve of the titration of weak acid with a strong base, is given below

Now choose the correct option among the following :

1) pH at point P = 0

1 1log ,

3 2pKa A where AA

0 is the initial concentration of weak acid

2) pH at point Q = pKa. –

1

log2

weak acid

Salt

3) pH at point 1 1 1

log2 2 2

R pKw pKa Salt

4) pH at point 1 1

log2 2

S pKw Base

34. It is found that 0.1 M solution of four sodium salts NaA, NaB, NaC and NaD have the following pHvalues. Which one of the corresponding acids is strongest?

1) NaD 11.0 2) NaC 10.0 3) NaB 9.0 4) NaA 7.0

35. An acid – base indicator has Ka = 3.0 10-5. The acid form of the indicator is red and the basic formis blue. The change in [H+] required to change to indicator form 75% red to 75% blue is1) 8 10-5 M 2) 9 10-5 M 3) 1 10-5 M 4) 3 10-4 M

36. 2.5 mL of 2

5M weak monoacidic base 12 01 10 25bK at C is titrated with

2

15 M HCl in water

at 250C. The concentration of H+ at equivalence point is 14 01 10 25wK at C

1) 3.7 10–13 M 2) 3.2 10–7 M 3) 3.2 10–2 M 4) 2.7 10–2 M

37. During the titration of 100 ml of a weak monobasic acid solution using 0.1 M NaOH, the solutionbecame neutral at 40 mL addition of NaOH and equivalence point was obtained at 50 mL NaOH

addition. The Ka of the acid is (log 2 = 0.3)

1) 1 10–7 2) 2 10–7 3) 3 10–7 4) 4 10–7

38. Equal volumes of the following solutions are mixed. In which of the following case the pH of resulting

solution will be the average of the two solutions. Give Ka(HCN) = 10–10 K

a of acetic acid is equal to K

bof ammonia1) HCl (pH = 2) and NaOH(pH = 12) 2) HCl (pH = 2) and HCl (pH = 4)

3) HCN(pH = 2) and NaOH (pH = 12) 4) CH3COOH (pH = 5) and NH

3(pH= 9)

39. Mark the incorrect statement regarding NH4F solution

1) Solution can act a buffer solution 2) For the solution, w

h

a b

KK

K K

3) Solution involves only anionic hydrolysis 4) Degree of hydrolysis is equal to (Kh)1/2

40. 0.2 mole of NH4Cl dissolved in 1000 gm of water lowered the freezing point by 0.710C. Degree of

dissociation of salt is 0.75. Kf for H

2O is 2 K kg mol–1. The degree of hydrolysis of salt is

1) 0.033 2) 0.066 3) 0.049 4) 0.099

41. The degree of hydrolysis of 102 M NH4CN in aqueous solution is 0.46. If the concentration of NH

4CN

increased four folds, the new degree of hydrolysis would be

given Ka(HCN) = 7.2 1010 and K

b(NH

4OH) = 1.8 105 at 25 C

1) 0.23 2) 0.46 3) 0.92 4) 0.100

42. Consider the titration curve shown below.

The titration curve represents the titration of:

1) a strong acid (beaker) with a strong base (buret).2) a weak acid (beaker) with a strong base (buret).3) a strong base (beaker) with a strong acid (buret).4) a weak base (beaker) with a strong acid (buret).

43. When bromocresol green is dissolved in aqueous solution, an equilibrium is established betweenbromocresol green (HIn, a weak monoprotic acid), the anion (conjugate base) of bromocresolgreen (In-) and H+ ions:

HIn(aq, yellow) <==> H+(aq, colorless) + In-(aq, blue-green)

If a small amount of bromocresol green is dissolved in a buffer solution at pH 11, the color of theresulting solution would be closest to:

1) colorless. 2) yellow. 3) blue-green. 4) red.

44. For an indicator, the value of pH = 2 when half of the indicator is present in the unionised form.

The pKIn

of the indicator is

1) 2 2) 3 3) 4 4) 5

45. Ksp

of CuS, Ag2S and HgS are 10–31, 10–44 and 10–54 respectively. Select the correct order for their

solubility in water

1) Ag2S > HgS > CuS 2) HgS > CuS > Ag

2S 3) HgS > Ag

2S > CuS 4) Ag

2S > CuS > HgS

46. Which of the following is correct decreasing order of solubility of AgCl ?

I) In water II) 0.1M NaCl III) 0.1M BaCl2

IV) 0.1M NH3

1) III > II > I > IV 2) IV > I > II > III 3) I > IV > II > III 4) I > II > III > IV

47. Ksp

of Pb Br2 is 8 10–5. If the salt is 80% dissociated in solution. The solubility of salt is

1) 0.016 M 2) 0.024 M 3) 0.034 M 4) 0.042 M

48. Solubility product constant (Ksp

) of salts of types MX, MX2 and M

3X at temperature ‘T’ are

4.0 10–8, 3.2 10–14 and 2.7 10–15, respectively. Solubilities (mole dm–3) of the salts at temperature

‘T’ are in the order :

1) MX > MX2 > M

3X 2) M

3X > MX

2 > MX 3) MX

2 > M

3X > MX 4) MX > M

3X > MX

2

49. The solubility product of AB is 4 10–10 at 180C. The loss of weight of precipitation of AB by washingit with 5 litres of water is1) 2 10–5 mol 2) 10–4 mol 3) 4 10–5 mol 4) 2 10–4 mol

50. The solubility of metal sulphides in saturated solution of H2S {[H2S] = 0.1 M} can be represented by

222

2 22 ; eq

M H SMS H M H S K

H

The value of Keq is given for few metal sulphide. If conc. of each metal ion in solution is 0.01 M, whichmetal sulphides are selectively ppt at total [H+] =1 M in saturated H2S solution

Metal sulphides MnS ZnS CoS PbS

22

2eq

M H SK

H

3 1010 3 10–2 3 3 10–7

1) MnS, ZnS, CoS 2) PbS, ZnS, CoS 3) PbS, ZnS 4) PbS

51. The solubility of Mg(OH)2 in a buffer of PH = 10 is found to be 0.0232 gm/lit. Molar solubility of

Mg(OH)2 in pure water would be (in mol/lit)

1) 510 2) 83.2 10 3) 53.2 10 4) 410

52. For sparingly soluble salt NaZn(UO2)3 (CH

3COO)

9 . nH

2O dissociates in Na+, Zn2+, 2

2UO and

CH3COO–, the relationship of its solubility product (K

sp) with its solubility(s) is

1) 21 213 .spK S 2) 21 143 .n nspK n S 3) 21 143 .spK S 4) 27 143 .spK S

53. The solubility of Mg(OH)2 is increased by adding of NH

4+ ion Mg(OH)

2 + 2NH

4+ 2NH

3 + 2H

2O +

Mg2+ If Ksp

(Mg(OH)2) = 110-11 and K

b for NH

4OH = 1.810-5, then K

c for the reaction is

1) 3.0810-2 2) 2.7110-2 3) 5.1010-3 4) 5.7710-2

53. A 0.10 M solution of fluoride ions is gradually added to a solution containing Ba2+, Ca2+ and Pb2+ ions,

each at a concentration of 110-3M. In what order, from first to last, will the precipi tates of

BaF2, CaF

2, and PbF

2 form ?

Solubility Product, Ksp

BaF2

1.8 10–7

CaF2

1.5 10–10

PbF2

7.1 10–7

1) CaF2, PbF

2, BaF

22) BaF

2, CaF

2, PbF

23) PbF

2, BaF

2, CaF

24) CaF

2, BaF

2, PbF

2

54. Addition of hydrochloric acid to a saturated solution of cadmium hydroxide (Cd(OH)2, K

sp = 2.5 x 10–14)

in water would cause:

1) the solubility of cadmium hydroxide to decrease.

2) the OH– concentration to decrease and the Cd2+ concentration to increase.

3) the concentrations of both Cd2+ and OH– to decrease.

4) the concentrations of both Cd2+ and OH– to increase

55. The solubility of CaCO3 = 8 mg/lit. Calculate the solubility product of BaCO

3 from this

information and from the fact that when Na2CO

3 is added slowly to the solution containing equimolar

concentration of Ca2+ and Ba2+. no precipitate of CaCO3 is formed until 80% of Ba+2 has been precipi-

tated as BaCO3

1) 1.28 10–9 2) 1.28 10–10 3) 1.28 10–11 4) 1.28 10–12

56. For the reaction 2

2Ag CN Ag CN , the equilibrium constant at 250C is 4 10–19. If a

solution is 0.1 M in KCN and 0.03 M in AgNO3 originally, at equilibrium, the conc. of Ag+ is

1) 7.5 10–16 M 2) 7.5 10–18 M 3) 1.25 10–19 M 4) 1.25 10–17 M

57. If 500 ml of 0.4 M AgNO3 is mixed with 500 ml of 2 M NH

3 is solution then what is the concentration

of [Ag(NH3)+] in solution?

Given kf1

[Ag(NH3)]+ = 103; k

f2[Ag(NH

3)2]+ = 104

A) 3.33 10–7 M B) 3.33 10–5 M C) 3 10–4 M D) 10–7 M

58. The solubility product of AgCl is 10–10 at 250C. A solution of Ag+ ion at a concentration of

4 10–3 M just fails to yields a AgCl with a concentration of 1 10–3 M of Cl– ion when the concentration of NH

3 in solution is 2 10–2 M. The equilibrium constant of

3 3 22Ag NH Ag NH

is

1) 10–8 2) 108 3) 2 10–8 4) 2 108

59. The solubility of silver formate in pure water is 10–2 mol/lit. Ka of formic acid is 1 10–5. The solubility

of silver formate in buffer solution of pH = 3 is

1) 10–1 mol/lit 2) 10–2 mol/lit 3) 10–3 mol/lit 4) 10–4 mol/lit

60. Ksp

for Sr F2 = 5 10–9 at 250C. How much NaF should be added to 100 ml of solution having

0.015M Sr+2 ions to reduce its concentration to 0.005M

1) 0.1764 gm 2) 0.0882 gm 3) 0.0661 gm 4) 0.0441 gm

61. 25 ml clear saturated solution of PbI2(aq) requires 12.5 ml of AgNO

3(aq) solution for complete neutral-

ization. Ksp

of PbI2 is 4 10–9. So conc. of AgNO

3 is

1) 2 10–3 M 2) 3 10–3 M 3) 4 10–3 M 4) 5 10–3 M

62. The solubility of the compound TL2S in pure water is 310-6 mol/lit. Assume that the dissolved S-2 ion

hydrolysis almost completely into HS- and that the further hydrolysis to H2S can be neglected.

K2(H

2S) = 10-14. The solubility product of the compound is

1) 9 10-12 2) 8.1 10-22 3) 8.1 10-12 4) 3.24 10-22

63. 300 ml of saturated clear solution of CaC2O

4(aq) requires 6 ml of 0.001 M KMnO

4(aq) in acid

medium for complete oxidation of C2O

4-2 ions. The K

sp of CaC

2O

4 is

1) 5 10-9 2) 5 10-10 3) 2.5 10-9 4) 2.5 10-10

64. How many numbers of mole of AgI which may be dissolved in 1 lit. of 1M CN- solution Ksp

for

AgI = 1 10-17 m2. Ag+ + 2 CN- Ag (CN)2- K

c = 9 1019 M-2

1) 0.245 2) 0.3675 3) 0.491 4) 0.735

65. Both Ag CNS and Ag Br is dissolved in a water. Ksp

of AgBr = 5 10-13 and Ksp

of Ag CNS = 1 10-12. The solubility of Ag Br in solution is1) 4 10-7 M 2) 2 10-7 M 3) 8.16 10-7 4) 6.2 10-7 M

66. The solubility product of AgCl is 1.8 × 10–10. The minimum volume (in L) of water required todissolve 1.9 mg of AgCl is approximately.

1) 10 2) 2 3) 1 4) 20

67. What is the aq. ammonia concentration of a solution prepared by dissolving 0.15 mole of

4NH CH3COO– in 1L H2O.[ )COOHCH(a 3

K =1.8×10–5 ; )OHNH(b 4K =1.8×10–5]

1) 8.3 ×10–4 2) 0.15 3) 6.4 ×10–4 4) 3.8 × 10–4

68. A 1 litre solution containing NH4Cl and NH4OH has hydroxide ion concentration of 10–6 mol/lit.Which of the following hydroxides could be precipitated when the solution is added to 1 litre solutionof 0.1 M metal ionsI Ag(OH) (KSP = 5 × 10–3) II Ca(OH)2 (KSP = 8 × 10–6)III Mg(OH)2 (KSP = 3 × 10–11) IV Fe(OH)2 (KSP = 8 × 10–16)1) I, II, IV 2) IV 3) III and IV 4) II, III, IV

69. Consider an aqueous solution that contains 0.10 M each of Pb2+, Hg2+ and Ni2+ ions. If a solution

containing 2 10–20 M S2– ion is added to the solution containing the metal ions then which sulphides

will precipitate from the solution

Given : KSP(PbS)

= 8 10–28; KSP(HgS)

= 4 10–53 and KSP(NiS)

= 3.2 10–19

1) PbS, HgS and NiS 2) PbS and HgS 3) HgS and NiS 4) HgS only

70. A weak monoacidic base is titrated against HCl of 0.3 M and the end point has reached on adding20 mL of the acid. To this solution 120 mg of NaOH if added, the pH of the resulting solution would be

[pKb of the base 4.2]

1) 4.2 2) 8.4 3) 9.8 4) 10.2

71. Solubility of a sparingly soluble salt Ba3(PO

4)2 in a mixture of

1

20 M BaCl

2( = 1) and

1

20 M

Ba(NO3)3 ( = 1) is [K

sp Ba

3(PO

4)2 = 10–7 M5. At mass Ba = 137, P = 31, O = 16]

1) 300.5 mg/lit 2) 601 mg/lit 3) 3005 mg/lit 4) 6010 mg/lit

72. The ionization constants for H2S are K

1 = 1.0 10–7, K

2 = 1.0 10–14. The pH of 0.005M Na

2S

solution is1) 2.3 2) 11.7 3) 10.7 4) 12.7

73. Solid BaF2 is added to a solution containing 0.1 mole of sodium oxalate solution (1 lit) until equilibrium

reached if the Ksp

of BaF2 and BaC

2O

4 is 10–6 mol3/ lit3 and 10–7 mol2/lit2

. The conc. C

2O

4–2 in solution

is1) 7.4 10–2 M 2) 3.7 10–2 M 3) 7.4 10–3 M 4) 3.7 10–3 M

74. Solution s a mixture of 0.05 M NaCl and 0.05M NaI. The concentration of iodide ion in the solutionwhen AgCl Just starts precipiating is equal to:(K

sp AgCl = 1 10–10 M2; K

sp AgI = 4 10–16 M2)

1) 410–6 M 2) 210–8 M 3) 210–7 M 4) 810–15 M

75. Which of the following is most soluble in water?1) MnS (K

sp = 8 10–37) 2) ZnS (K

sp = 7 10–16)

3) Bi2S

3 (K

sp = 1 10–72) 4) Ag

3(PO

4) (K

sp = 1.8 10–18)

76. At what 23

Br

CO

does the following cell have its reaction at equilibrium?

Ag(s) |Ag2CO

3(s)| Na

2CO

3(aq)| |KBr(aq)| AgBr(s)| Ag(s)

Ksp

= 8 10–12 for Ag2CO

3 and K

sp = 4 10–13 for AgBr

a) 71 10 b) 72 10 c) 73 10 d) 74 10

Assertion (A) & Reason (R) type questions : 1) Both A and R are true and R is correct explanation of A

2) Both A and R are true and R is not correct explanation of A3) A is true, R is false 4) A is false, R is true

77. Assertion (A) : A solution whose pH is 6.9, must be acidic

Reason (R) : In an acidic solution H+ ion concentration must be greater than wK

78. Assertion (A) : Water acts as levelling solvent for various acidsReason (R) : Levelling effect of water is due to its high dielectric constant and strong proton accept-ing tendency

79. Assertion (A) : pH of buffer solution changes with change in temperature

Reason (R) : KW

of water changes with change in temperature

80. Assertion (A) : A bowler bowling the last crucial over in an India – Pakistan 20 – 20 match breathesheavily due to excitement and tension, leading to significant change in the pH of blood

Reason (R) : pH of blood =

3

2 3

logHCO

pKaH CO

81. Assertion (A) : Addition of a small amount of sodium acetate to a dilute solution of acetic acid doesnot effect the pH value

Reason (R) : Buffer solutions have a definite pH value

82. Assertion (A) : A buffer solution has a capacity to resist the change in pH value on addition of small amount of strong acid or base to it

Reason (R) : pH value of buffer solution does not change on dilution or on keeping for long standing

83. Assertion (A) : Aqueous solution of CH3COONa is alkaline in nature

Reason (R) : Acetate ion under goes anionic hydrolysis

84. Assertion (A) : Aqueous solution of CH3COONH

4 is found to be neutral

Reason (R) : Because this salt does not undergo hydrolysis

85. Assertion (A) : pKa of a weak acid becomes equal to pH of the solution at the mid point of its titration

Reason (R) : The molar concentrations of proton aceptor and protondonor become equal at the midpoint of titration of weak acid

86. Assertion (A) : Na2CO

3 does not affect the pH of pure water on dissociation

Reason (R) : Salt of strong acid and strong base do not undergo hydrolysis

87. Assertion (A) : Equal number of millimoles of CH3COOH and NaOH when mixture together, the

resulting aqueous solution becomes alkalineReason (R) : Since the base is stronger, the salt formed undergoes anionic hydrolysis

88. Assertion(A): Dilution of an aqueous solution of salt of strong a acid and weak base will cause an increase in pHReason(R): Degree of ionisation of weak base will increase with dilution

89. Assertion(A): In an acid base titration involving a strong acid and a weak base, methyl orange can be used as an indicatorReason(R): Methyl orange changes its colour in the pH range 3 to 5

90. Assertion(A): In acidic medium Zn+2 is not precipitated by S–2 IonsReason(R): Zn S is soluble in aqueous solution

91. Assertion(A): The pH of an aqueous solultion of aceticacid remains unchanged on the addition of sodium acetateReason(R): The ionisation of acetic acid is supressed by the addtion of sodium acetate.

92. Assertion (A) : The addition of silver ions to a mixture of aqueous sodium chloride and sodiumbromide solution will first precipitate AgBr rather than AgCl

Reason (R) : The value of Ksp

of AgCl < Ksp

of AgBr .

93. Assertion (A) : To precipitate the cations of fourth group in qualitative analysis, medium is made alkaline before passing H

2S gas

Reason (R) : This is done to suppress the ionisation of H2S in fourth group analysis

Comprehensions type questions : Passage - 1:

The pH value for pure water is 7.0 at 270C, whereas natural rain water is slightly acidic. This is mainly

due to presence of SO3 and NO

2 gas obtained by oxidation of SO

2 and NO gas. In some causes acid

rain due to SO3 and NO

2 consist of pH of 4.5 to a value as low as 1.7. At 270C the acidity constant are

2 2 3SO aq H O l HSO aq H aq

3 2

12

10a

H HSOK M

SO

23 3HSO aq SO aq H aq

23 7

2

3

10a

SO HK M

HSO

22 2 3 2SO aq H O aq SO aq H aq

9

1 210a a aK K K M

2H O H OH

Kw

= 10–14

94. The pH of 0.01 M aqueous solution of Na2SO

3 will be (Assume hydrolysis proceeds only one step)

1) 8.5 2) 9 3) 9.25 4) 9.5

95. If rain water consists of 2.463 litre SO3 gas dissolved in 1 litre water at partial pressure of 2 atm, then

pH of solution is(R = 0.0821 litre atm/K mole)(log 2 = 0.3)1) 0.7 2) 1.4 3) 0.6 4) 0.4

96. In acid rain in Assam it was found that 1 litre rain water consist of 2.463 litre equimolar mixture of SO3

and NO2 gas dissolved at a partial pressure of 0.1 atm. Find out the pH of the solution if HNO

2

produced is 60% dissociated under given condition at 270C

1) 2 2) 2.75 3) 2.25 4) 1.85Passage -II:

Three bottles labelled A, B, C contain 150 ml of 0.1 M weak mono protic acid, 50 ml 0.1 M strongmono acidic base, 150 ml 0.1 M strong monoprotic acid respectively a student performs some experi-ments then the following observations are made

a) When solution A and B are mixed then it form a buffer of pH = 4.7b) When B and C mixed then solution is acidicc) When A and C are mixed then solution is acidic and pH is 2 – log 5

97. What would be ionisation constant of weak acid

1) 2 10–4 2) 10–5 3) 2 10–6 4) 5 10–6

98. What will be pH of solution when B and C are mixed completely1) 2 – log 5 2) 5 – log 2 3) 2 4) 1

99. What will be degree ionisation when weak acid solution is mixed with strong acid

1) 5 10–3 2) 2 10–3 3) 2 10–4 4) 5 10–4

Passage - III:

Aqueous 200 ml 0.1 M H2A solution when titrated against 0.1 M NaOH shows different results,

in presence of different indicators. For phenolphthalein indicator it is converted to Na2A and with methyl

orange it is converted to NaHA

Ka1 H

2A = 10–3, Ka

2 H

2A = 10–6

H2A + NaOH NaHA + H

2O (methyl orange)

NaHA + NaOH Na2A + H

2O (Phenol phthalein)

100. When 100 ml of NaOH is added in the presence of methyl orange indicator pH of solution is

1) 3.5 2) 4.5 3) 3 4) 4

101. When 200 ml of NaOH is added the pH of the solution is1) 3.5 2) 4.5 3) 3 4) 4

102. When 400 ml of NaOH is added in the presence of phenol phthalein indicator. The pH ofsolution is1) 8 2) 4.74 3) 9.26 4) 7

Passage – IV : A weak Base BOH was titrated against a strong Acid The PH at 1/4 the equalivalent point was 9.24. Now strong base 6 m eq. added to it. Total salt converted to weak base . The total volume was 50 ml.

103. The PKb of Base is1) 4.76 2) 5.061 3) 5.23 4) 5.36

104. The pH of the solution after addition of strong Base is1) 9.22 2) 10.22 3) 11.22 4) 12.22

Passage : V The pH of pure water at 250C and 600C is 7 and 6.5 respectively. HCl gas is passed throughwater at 250C till the resulting 1 litre solution which acquires a pH of 3. Now 4 10–3 mole of NaCN areadded to this solution. The fresh 0.1M HCN solution has pH is 5.2. Now half part of solution obtainedafter addtion of NaCN. 0.25 milli moles of NaOH added and other second part add 0.5 milli mole ofHCl is added

105. The heat of formation of water from H+ and OH– is1) 13.06 Kcal 2) –16.32 Kcal 3) 16.32 Kcal 4) –13.06 Kcal

106. The volume of HCl passed through the solution at 250C and 1 atm is1) 24.46 ml 2) 2.446 ml 3) 0.2446 ml 4) 244.6 ml

107. The dissociation constant of HCN is1) 4.0 10–10 2) 4.0 10–6 3) 4.0 10–4 4) 4.0 10–8

108. The pH of the solution after addition of NaCN is1) 9.87 2) 8.87 3) 6.87 4) 5.87

109. The pH of solution after addition of 0.5 milli mole of HCl is1) 9.68 2) 9.4 3) 8.4 4) 8.7

Passage – VI :

0.1 M CH3COOH solution is titrated against 0.05 M NaOH solution. pH of 0.1 M CH

3COOH is 3.

110. The pH of solution at 1/4th neutralization of acid is

1) 4.21 2) 4.52 3) 5.12 4) 5.47

111. The pH of solution at 3/4th neutralization of acid is

1) 4.21 2) 4.52 3) 5.12 4) 5.47

Passage – VII : A one litre buffer solution containing 0.5 M CH

3COOH and 0.25 M CH

3COONa. The pKa value of

acetic acid is 4.74. The solubility product of Ca(OH)2 Al(OH)

3, Cr(OH)

3 are 5.5 10-6, 1.3 10-33,

6.3 10-31 in pure water respectively.

112. PH of the buffer solution is1) 5.04 2) 4.74 3) 4.04 4) 4.44

113. If 0.25 mole of HCl is added to the buffer solution then the pH is1) 3.86 2) 4.74 3) 4.86 4) 2.43

114. If 0.25 mole NaOH is added to the buffer solution than the pH is1) 4.04 2) 4.74 3) 4.44 4) 5.04

115. AlCl3 is added to the a buffer solution then the concentration of Al+3 present in the solution is

1) 1.82 10-5 M 2) 6.75 10-5 M 3) 6.75 10-4 M 4) 1.82 10-4 M

116. One lit solution containing Ca+2, Al+3, Cr+3 in 0.1 M concentration each. The solution is mixed with onelit. buffer solution. Which ion remains un precipitated1) Ca+2 2) Al+3 3) G+3 4) All

Passage – VIII

Arsenic sulphite As2S

3 is a sparingly soluble salt and presence of As+3 Ion in solution is observed by

the formation of its precipitate

The solubility of As2S

3 is observed to be

9110

48M in a solution of 10–2 M Na

2S solution at 25oC.

Assuming no hydrolysis of cationic or Anionic part

117. The Ksp

value of As2S

3 at 25oC

1) 241

10576

2) 101

1036

3) 221

10144

4) 91

1024

118. The solubility of As2S

3 at 25oC is a solution of 33 10 M AsCl

3 solution is, assuming no hydrolysis

1) 61

10144

M 2) 71

10180

M 3) 61

1036

M 4) 41

1096

M

119. If the hydrolysis of sulphide Ion is to be considered, then the solubility of As2S

3 in pure water is

1 2

7 142 210 , 10a aK H S K H S

1) 41.67 10 M 2) 55.4 10 M 3) 37.2 10 M 4) 26 10 M

Passage - IX:

AgCNS and AgBr both dissolved in water Ksp

AgCNS = 5 10–13 Ksp

AgBr = 1 10–12

120. The solubility of AgCNS in water is

1) 4 10–7 M 2) 8.16 10–7 M 3) 2 10–7 M 4) 6.08 10–7 M

121. The solubility of AgBr in water is

1) 4 10–7 M 2) 8.16 10–7 M 3) 2 10–7 M 4) 6.08 10–7 M

Passage - X:

A solution contains a mixture of Ag+(0.1 M) and 22Hg (0.1 M) which are to be separated by

selective precipitation

Ksp

AgI = 1.0 10–17 Ksp

of Hg2I2 = 1 10–27

122. The maximum concentration of I– ion at which one of them gets precipitated completely is and first

precipitating ion is

1) 10–16 M, Ag+ 2) 10–16 M, Hg2+2 3) 10–13 M, Ag+ 4) 10–13 M, Hg

2+2

123. The percentage of metal ion precipitated is

1) 99% Ag+ 2) 99% Hg2

2+ 3) 99.9% Ag+ 4) 99.9% Hg2

2+

Passage – XI :

The salt Zn(OH)2 is involved in the following two equilibria Zn(OH)

2(s) Zn+2 (aq) + 2 OH –(aq)

Ksp

= 1 10–17

Zn(OH)2(s) + 2OH–(aq) [Zn(OH)

4]–2 (aq) K

c = 0.1

124. The pH at which the solubility of Zn(OH)2 is minimum

1) 11 2) 8 3) 9 4) 10

125. The solubility of salt is

1) 1 10–10 2) 1 10–9 3) 2 10–10 4) 2 10–9

Passage – XII :

A solution containing zinc and manganese ions each at a concentration of 0.01 mol/dm3 is saturated

with 0.1 M H2S. K

sp Zn S = 1 10–22 mol2/lit2. K

sp Mn S = 1 10–16 mol2/lit2 . K

1, K

2 for H

2S are

1.0 10–7 and 1.0 10–14

126. The pH at which the MnS will start precipitate1) 3 2) 4 3) 5 4) 6

127. The conc. of Zn+2 remaining when MnS starts precipitate

1) 10–8 mol/lit 2) 10–9 mol/lit 3) 10–10 mol/lit 4) 10–11 mol/lit

Passage – XIII :The acid ionisation constant for

Zn+2 + H2O Zn(OH)+ + H+ is 1.0 10-9

128. The basic dissociation constant of Zn(OH)+ is1) 10-4 2) 10-5 3) 10-6 4) 10-7

129. The pH of 0.001 M solution of ZnCl2 in above problem is

1) 4 2) 5 3) 6 4) 7

Passage - XIV

Solid AgNO3 is gradually mixed with equimolar solution of NaBr and NaCl, each having

molarity 0.02 M

KSP(AgBr)

= 5 10–16 KSP(AgCl)

= 1.0 10–10

130. The minimum [Ag+] required for just the start of precipitation of AgBr

1) 5 10–14 M 2) 2 10–15 M 3) 2.5 10–14 M 4) 5 10–15 M

131. [Ag+] required to just start the precipitation of AgCl is

1) 5 10–8 M 2) 2.5 10–8 M 3) 5 10–9 M 4) 2.5 10–19 M

132. The concentration of Br– ion left in the solution when precipitation of AgCl just start

1) 1.0 10–9 M 2) 2 10–7 M 3) 5 10–9 M 4) 1.0 10–7 M

Passage - XV Colligative property measurement is one of the techniques used in the measurement of chemicalquantities with reasonable accuracy.

If a 40.65 gm sample of K2SO

4 and BaSO

4 is dissolved in 900 gm of pure water to form a solution

‘A’ is 570C, its vapour pressure is found to be 39.6 torr while vapour pressure of pure water at 570C is

40 torr. Density of solution A is 1.24 gm/ml.

In a different experiment when small amount of pure BaSO4 is mixed with water at 570C it gives the

osmotic rise of 4.05 10–5 atm.

133. Percentage of K2SO

4 in the sample is

1) 65.75% 2) 71.34% 3) 60.35% 4) 78.74%

134. Solubility product of BaSO4 in water at 570C is

1) 5 10–19 2) 3.125 10–13 3) 5.625 10–13 4) 2.25 10–12

Passage - XVI:

Radiochemical techniques can be used to determine solubility product estimation. The measure-ment of radioactivity can be used to find the concentration in a solubility equilibrium giving a fair idea

about various equilibrium concentrations. In an experiment, 50.00 ml of a 0.010 M AgNO3 solution

containing a silver isotope with a radioactivity of 75,000 counts per min per ml were mixed with 100 ml

of a 0.03 NaIO3 soluition. The mixed solution was diluted to 500 ml and filtered to remove all of the

AgIO3 precipitate leaving behind a radioactive solution. Molar mass of AgIO

3 = 285 g/mol. The re-

maining solution was found to have a radioactivity of 50 counts per min per ml.

135. Find the mass of the ppt. of AgIO3 obtained separated

a) 142 mg b) 283 mg c) 383 mg d) 483 mg

136. The Ksp

of AgIO3 silver (radio active) are :

a) 3.3 10–16 b) 3.3 10–8 c) 5.3 10–10 d) 5.3 10–8

137. The % of unprecipitated silver ions is :a) 0.15% b) 0.37% c) 0.67% d) 0.97%

One or more than one correct answer type questions :

138. In 0.020 M carbonic acid solution

1) H2CO

3 is stronger acid than HCO

3- 2 )

22 3 3 1 2

2 , .eq a aH CO H CO K K K

3) 2

3 3HCO CO 4) It can be said 21a aK K

139. For pure water1) pH increases with increase in temperature 2) pH decreases with increase in temperature

3) pH = 7 at temperature of 250C

4) pH increases at low temperature but decreases at high temperatures

140. In the following reaction

3 2

2 2 3 26 5Al H O H O H O Al H O OH

A B C D1) A is an acid B is a base 2) A is a base B is an acid3) C is conjucate acid of B and D is conjucate base of A4) C is conjucate base of B and D is conjucate acid of A

141. Which is/are wrong statements1) All anhenius acids are Bronsted acids but all arrhenius bases are not Bronsted bases2) All Bronsted bases are Lewin bases3) All Bronsted acids are Lewin acids4) Conjugate acids of strong base is a strong acid

142. Which of the following is/are true about alkanity?1) Alkali metal hydroxides are water-soluble ionic solids, most familiar bases2) Alkaline earth oxides, such as CaO are weaker bases than corresponding hydroxides3) 0.28 g of lime (CaO) in 1 lit. water gives a solution of pH = 12

4) 10–7M NaOH solution has pH value 7

143. In photography, equionole is used as developer according to following reaction

Which of the following describe (s) the role of equinol in this reaction?

1) It acts as an acid 2) It acts as a weak base3) It acts as an oxidising agent 4) It acts as a reducing agent

144. 0.56 gm CaO lime is dissolved in 100 ml water and made a saturated solution (kw

= 10–13). The correct

statements are

1) Concentration of OH– = 0.2 M

2) Conc. H+ would be = 5 10–13 M

3) Degree of dissociation of water in the solution 9 10–15

4) If 1.12 gm of CaO added to 100 ml at same temperature then conc. OH– is = 0.4 M

145. Which of the following is true for alkaline aqueous solution?

1) 2wpkpH 2) pH > pOH 3)

2wpkpOH 4) pH < pOH

146. The acid dissociation constant for 3

2 6Al H O

is 1.410-5. It suggests

1) H2O molecules in the hydrated cation are much stronger proton donors than are free

solvent water molecules

2) Ionisation : 3

2 6Al H O

(aq) AlAl3+ (aq) + 6H

2O

3) Ionisation : 3

2 6Al H O

(aq) + H

2O(l) H

3O+ (aq) + Al(H

2O)

5 (OH)2+ (aq)

4) Its pH might be more than 7.

147. Which of the following statements are correct?1) NH

4OH is a weak base 2) NH

4Cl forms an acidic solution in H

2O

3) H3BO

3 tripotic acid 4) CH

3COONa forms a basic solution in water

148. Which of the following combination of solutes would result the formation of a Buffer solution1) NH3 + NH4Cl 2) CH3COOH + NaOH in 2 : 1 molar ratio3) NH3 + HCl in 2 : 1 molar ratio 4) CH3COOH + NaOH in 1 : 2 molar ratio

149. Which of the following statements are correct

1) Larger the value of dissociation constant, greater is the strength of acid2) All Bronsted bases are Lewis bases but all Bronsted acids are not Lewis acids3) Degree of dissociation of water increases with the rise of temperature4) Degree of hydrolysis at salt of weak acid and weak base does not change with dilution

150. An acid-base indicator Hln exists 50% dissociated at pH = 9. The acid colour of the indicator is yellowwhile its base colour is red. The red colour predominates when the concentration of conjugate base is atleast 8 times that of the acid while for yellow colour to predominate, the concentration of the speciespossessing this colour must be at least 20 times that of the species possessing red colour. Now read thefollowing statements and choose the correct statement(s) from the key given below1) The pH range of the indicator is 7.7 – 9.92) The pH range of the indicator is 8.2 – 10.3

3) The indicator may serve to indicate the end point of the titration of HCl vs. NH4OH

4) The indicator may serve to indicate the end point of the titration between HCl and NaOH

151. An acid-base indicator has Kb equal to 1.0 10–6. The acid form of the indicator is blue and the basic

form is red then1) At pH 8, solution remains complete (99%) red 2) At pH 10, solution remains complete (99%) red3) At pH 6, solution remains complete (99%) blue 4) At pH 8, solution remains complete (99%) blue

152. Let the colour of the indicator HIn (colourless) will be visible only when its ionised form (pink) is 25% or

more in a solution. Suppose HIn (pKa = 9.0) is added to a solution of pH = 9.6 predict what will happen

(Take log 2 = 0.3)

1) Pink colour will be visible 2) Pink colour will not be visible

3) % of ionised form will be less than 25% 4) % of ionised form will be more than 25%

153. Choose the correct alternatives

1) Ksp

of Fe(OH)3 in aqueous solution is 3.8 10–38 at 298 K. The concentration of Fe+3 will increases

with H+ ion concentration decreses

2) In a mixture of NH4Cl and NH

4OH in water, a further amount of NH

4Cl is added. The pH of mixture

will decreases

3) An aqueous solution of each of the following salts NH4I, Cr(NO

3)3, KCN will be basic, acidic

neutral respectively

4) Degree of hydrolysis of 0.1M CH3COONH

4, 0.2 M CH

3COONH

4 is same

154. On mixing equal volumes of the following solutions, precipitation of AgCl will occur with (Ksp

for AgClis 1.8 10–10)1) 10–3 M (Ag+) and 10–3 M (Cl –) 2) 10–4 M (Ag+) and 10–4 M (Cl –)3) 10–5 M (Ag+) and 10–5 M (Cl –) 4) 10–10 M (Ag+) and 10–10 M (Cl –)

155. Which about solubility product is correct1) If ionic product < solubility product, solution is unsaturated2) For AlCl

3 K

sp = 27S4, Hen ‘S’ solubility in H

2O

3) If ionic product > solubility product, precipitate occurs4) Solubility AlCl

3 in 0.1 M KCl is S.Then K

sp = 0.001S

156. In mixing equal volumes of the following solutions, precipitation of AgCl will occur(K

sp of AgCl = 1.8 10-10)

1) 10-5 M Ag+ and 10-5 MCl- 2) 10-10 M Ag+ and 10-10 MCl-

3) 10-3 M Ag+ and 10-6 MCl- 4) 10-4 M Ag+ and 10-4 MCl-

Matching type questions :

157. Match the following Column – I with Column – II Column – I Column – II

a) NH3

p) Aqueous solution is alkaline in nature

b) O2– q) Lewis base

c) 3HCO r) Does not have a conjugate base

d) KMnO4

s) Amphoteric in nature

158. Column – I Column – II

A) CH3COOH P) Weak electrolyte

B) NH4Cl Q) Strong electrolyte

C) NH4OH R) On dilution of aqueous solution, the

D) CH3COONa degree of dissociation increases

S) pH – increases on dilution of

aqueous solution.

T) pH - decreases on dilution of aq. solution

159. Match the following question Column I with Column II

Column - I Column - II

A) [H+] in an aqueous solution of NH4CN p)

1 2

1/ 2

a ak k

B) [H+] in an aqueous solution of NaHCO3

q)

1

2w a

b

k k

k

C) [H+] in an aqueous solution of NH4HCO

3r)

2 1

1

2w

a a

b

kk k

k

D) 23CO in 0.01M H

2CO

3s) Does not depend on the

concentration of salt

t) 2ak

160. Match the mixture in Column – I with their corresponding characteristic in Column – II

List – I List – II

a) CH3COOH (pK

a = 4.74; 0.1 M) + p) Acidic buffer at its maximum capacity

CH3COONa(0.1 M)

b) CH3COOH(0.1 M) + HCl (0.1M) q) buffer solution

c) CH3COOH (pK

a = 4.74; 0.1 M) + r) pH < 7 at 250C

NH4OH(pk

b = 4.74, 0.1 M)

d) CH3COONa(300 ml of 0.1 M) + s) pH = 7 at 250C

HCl (100 ml of 0.1 M)Note : Equal volume of each component in each mixture is to be taken

161. Match the following Column – I with Column – II Column – I (Solution 0.1 M) Column – II

a) NaCl p) pH will not vary with dilutionb) KCN q) Buffer solution

c) CH3COONa r) pH is almost 7

d) CH3COONH

4s) Hydrolysis of only anion takes place

162. H3PO

4 is a triprotic acid with K

1 = 10–4, K

2 = 10–7, and K

3 = 10–10

List – I List – II (pH of the solution)

a) Equimolar mixture of NaH2PO

4 (0.1 M) p) 13

and Na3PO

4(0.1 M)

b) H3PO

4 (0.1 mol) + NaOH (0.2 mol) in 1 litre solution q) 5.5

c) Na3PO

4 (0.1 mol) + NaOH (0.1 mol) in 1 litre solution r) 8.5

d) H3PO

4 (0.1 mol) + KOH (0.25 mol) in 1 litre s) 10

163.Column – I Column – IIa) PK

b for X– (K

a of HX = 10–6) p) 6.9

b) pH of 10–8 MHCl q) 8c) pH of 10–2 M acetic acid (K

a = 1.6 10–5) r) 3.3

d) pH of solution obtained by mixing equal volumes of solutions with pH = 3 and pH = 5 s) 3.4

164. Column – I Column – IIa) CH

3COOH

, CH

3COONa mixture in p) pH increases on addition of HCl

1 : 1 molar ratiob) NH

4OH, NH

4Cl mixture in 1 : 1 molar ratio q) pH decreases on addition HCl

c) CH3COOH solution r) pH remains same on dilution

d) NH4OH solution s) pH increases on dilution

165. Column – I Column – IIa) CuSO

4 Solution p) cationic hydrolysis

b) Na2CO

3 solution q) Anionic hydrolysis

c) CH3COONH

4 solution r) Neutral solution

d) NaCl solution s) Acidic Solution

166. List – I List – IIa) Equimolar mixture of a strong acid and p) Acidic a strong baseb) Equi-equivalent mixture of a strong acid q) Basic and a weak basec) Equi-equivalent mixture of a strong base r) Neutral and a weak acidd) Equi-equivalent mixture of a weak acid s) Can’t be predicted and a weak base

166. List – I List – II

a) CuSO4 solution p) Acidic nature

b) Na2CO

3 solution q) Basic nature

c) CH3COOH + CH

3COONa r) Cationic hydrolysis

solution

d) NH4OH + NH

4Cl solution s) Anionic hydrolysis

167. Match the following Column – I with Column – II

List – I List – II

a) CuSO4

p) Catonic hydrolysis

b) Na2CO

3q) Anoinc hydrolysis

c) NaCl r) pH < 7

d) CH3COONH

4s) pH = 7

168. For the following matching take the concentrations of the both the solutions being titrated to be equal to

0.1 M, and ka of CH

3COOH = 2 10–5, k

a1 of H

2CO

3 = 10–7, k

a2 of H

2CO

3 = 10–11,

kb of NH

3 2 10–5)

List – I (Titrations) List – II (Properties)

a) CH3COOH + NaOH p) Approximate shape of the titration curve will be

b) NH4Cl + NaOH q) Phephthalein (pk

ln = 9) can be used for end

point detection

c) Na2CO

3 + HCl (upto 1st equivalence point) r) At equivalence point

water < 1.8 10–9

d) HCl + NaOH s) At equivalence point, pH >7

169. Match the following

List – I List – II

a) Acid indicator p) Colour of ionized form of indicator appears in acidic mediumb) Base indicator q) Colourless in acidic mediumc) Phenolphtalein r) Colour of ionized form of indicator appears in basic mediumd) Methyl orange s) Colour of unionized form of indicator appears in acidic medium

170. List – I List – II

(Salt) (Relation between solubility S mol L–1 and Ksp

)

a) Ag2CrO

4p)

1/5

108

spKS

b) AgCNS q) Conc. of cation is 2S

c) Ca3(PO

4)2

r)

1/3

4

spKS

d) Hg2Cl

2s) S = (K

sp)1/2

Numerical type questions :

171. 0.16 gm of N2H

4 are dissolved in water and the total volume made upto 500 ml. Calculate the percent-

age of N2H

4 that has reacted with water in this solution. The K

b for N

2H

4 is 4 10–6 M

172. The pH of glycine at the first half equivalence point is 2.40 and that at second half equiva-lence paint is 9.60. At the equivalence point (The first inflection point) The pH is

173. 50 mL of 0.05 M Na2CO

3 is titrated against 0.1 M HCl. On adding 37.5 mL of HCl, pH of the solution

will be [Given : For H2CO

3, pK

a1 = 6, pK

a2 = 10.33 log 3 = 0.47, log 2 = 0.30] (Express answer the

nearest integer

174. pH of the solution containing 50.0 ml of 0.3 M HCl and 50.0 ml of 0.4 M NH3 is

[pKa (NH4+) = 9.26]

Multiply your answer with 102 and fill in the answer key ........

175. CH3NH

2 (0.1 mole, K

b = 5 10–4) is added to 0.08 moles of HCl and the solution is diluted to one

litre. The resulting hydrogen ion concentration is. Multiply your answer by 1011 and fill in the answer key

........

176. A solution of weak acid was titrated with base NaOH. The equivalent point was reacted when36.12 ml of 0.1 M NaOH have been added. Now 18.06 ml of 0.1 M HCl was added to this solutionthen pH was 5. What is the pKa of acid

177. A certain buffer solution equal concentration of HX and X–. The Kb for X– is 10–10. The pH of the buffer

is

178. Find the pH of mixture obtained by mixing equal volume each of 0.1M Na3PO

4 and 0.1M NaH

2PO

4 at

TK.

Given : 1 2,a aK K and

3aK of H

3PO

4 at TK are respectively 10–3M, 10–6M and 10–12M

179. 50 ml 0.2M CH3COOH (K

a = 10–5) is titrated with 0.2M NaOH. The pH at equivalence point is

180. Ionisation constant of HA(weak acid) and BOH (weak base) are 3 ́ 10–7 each at 298 K. Calculate thedegree of hydrolysis of 0.1 MBA at the dilution of 10 lit. The value is multiply with 8 and fill the numberin answer ky

181. 250 mL a saturated solution of calcium oxalate required 6.4 mL of 0.001 M KMnO4 solution in acid

medium for complete oxidation of oxalate ions. Hence the solubility product of calcium oxalate is : x ×10–9. The value of ‘x’ would be ?

182. M(OH)X

has Ksp

= 27 10–12 and solubility in water is 10–3 M. The value of ‘X’ is

183. The solubility product constant (Ksp) of M(OH)

2 is 195 10 at 250C. pH of a saturated aqueous solution of

M(OH)2 when large excess of base is dissolved at 250C would be

184. After solid Sr CO3 was equilibrated with a pH = 8.60 buffer, the solution was found to have

[Sr2+] = 2.2 ́ 10–4 M. Determine the solubility product of SrCO3. K

2 for H

2CO

3 = 4.7´10–11 . Given 10–

8.6 = 2.51 ´ 10–9 . Answer is .........´ 10–10

185. Ag+ + 2CN– Ag(CN)2– K

f = 1.0 ́ 1019 the solubility product of AgI is 1 ́ 10–17 mol2/lit2 The

number of mili moles of AgI required to dissolve 1 litre of 1 M CN– solution to form equilibrium is.Answer corrected to whole number