NEET AIPMT Chemistry Chapter Wise Solutions – Equilibrium

NEET AIPMT Chemistry Chapter Wise SolutionsPhysicsBiology

1. The equilibrium constants of the following are (NEET 2017, 2007, 2003)

(a) K₂K₃³/K₁
(b) K₂K₃/K₁
(c) K₂³K₃/K₁
(d) K₁K₃^3/K₂

2. Concentration of the Ag⁺ ions in a saturated solution of Ag₂C₂0₄ is 2.2 x 10^-4 mol L^-1. Solubility product of Ag₂C₂0₄ is (NEET 2017)
(a) 2.66 x 10^-12
(b) 4.5 x 10^-11
(c) 5.3 x 10^-12
(d) 2.42 x 10^-8

3. A 20 litre container at 400 K contains C0₂(g) at pressure 0.4 atm and an excess of SrO (neglect the volume of solid SrO). The volume of the container is now decreased by moving the movable piston fitted in the container. The maximum volume of the container , when pressure of C0₂ attains its maximum value, will be
(Given that : SrC0_3(s)== SrO_(s) + C0_2(g),Kp = 1.6 atm) (NEET 2017)
(a) 10 litre
(b) 4 litre
(c) 2 litre
(d) 5 litre

4. The percentage of pyridine (C₅H₅N) that forms pyridinium ion (C₅H₅N⁺H) in a 0.10 M aqueous pyridine solution (K_b for C₅H₅N = 1.7 x 10^-9) is (NEET-II 2016)
(a) 0.0060%
(b) 0.013%
(c) 0.77%
(d) 1.6%

5.The solubility of AgCl(s) with solubility product 1.6 x 10^-10 in 0.1 M NaCl solution would be (NEET-II 2016)
(a) 1.26 x 10^-5 M
(b) 1.6 x 10^-9 M
(c) 1.6 x 10^-11 M
(d) zero.

6. Which of the following fluoro-compounds is most likely to behave as a Lewis base? (NEET-II 2016)
(a) BF₃
(b) PF₃
(C) CF₄
(d) SiF₄

7. MY and NY3, two nearly insoluble salts, have the same K_sp values of 6.2 x 10^-13 at room temperature. Which statement would be true in regard to MY and NY3? (NEET-1 2016)
(a) The salts MY and NY3 are more soluble in 0.5 M KY than in pure water.
(b) The addition of the salt of KY to solution of MY and NY3 will have no effect on their solubilities.
(c) The molar solubilities of MY and NY3 in water are identical.
(d) The molar solubility of MY in water is less than that of NY3.

8 . If the equilibrium constant for (2015)

(a) 1/2K
(b) K
(c) K²
(d) K½

9. What is the pH of the resulting solution when equal volumes of 0.1 M NaOH and 0.01 M HCl are mixed? (2015)
(a) 2.0
(b) 7.0
(c) 1.04
(d) 12.65

10. Aqueous solution of which of the following compounds is the best conductor of electric current? (2015)
(a) Hydrochloric acid, HCl
(b) Ammonia, NH₃
(c) Fructose, C₆H₁₂0₆
(d) Acetic acid, C₂H₄0₂

11. Which one of the following pairs of solution is not an acidic buffer? (2015)
(a) CH₃COOH and CH₃COONa
(b) H₂C0₃ and Na₂C0₃
(c) H₃PO₄ and Na₃P0₄
(d) HCIO₄ and NaCIO₄

12. The K_sp of Ag₂Cr0₄, AgCl, AgBr and Agl are respectively, 1.1 x 10^-12,1.8 x 10^-10,5.0 x 10^-13, 8.3 x 10^-17. Which one of the following salts will precipitate last if AgN0₃ solution is added to the solution containing equal moles of NaCl, NaBr, Nal and Na₂Cr0₄? (2015, Cancelled)
(a) AgBr
(b) Ag₂Cr0₄
(c) Agl
(d) AgCl

13. Which of the following statements is correct for a reversible process in a state of equilibrium? (2015, Cancelled)
(a) ΔG° = -2.30 RT log K
(b) ΔG° = 2.30 RT log K
(c) ΔG = -2.30 RT log K
(d) ΔG = 2.30 RT log K

14. If the value of equilibrium constant for a particular reaction is 1.6 x 10¹², then at equilibrium the system will contain (2015, Cancelled)
(a) mostly products
(b) similar amounts of reactants and products
(c) all reactants
(d) mostly reactants.

15.Which of the following salts will give highest pH in water? (2014)
(a) KCI
(b) NaCl
(c) Na₂C0₃
(d) CuS0₄

16.Using the Gibb’s energy change, ΔG° = +63.3 kJ, for the following reaction,

the K_sp of Ag₂C0_3(s) in water at 25 °C is (R = 8.314 J K^-1 mol^-1) (2014)
(a) 3.2 x 10^-26
(b) 8.0 x 10^-12
(c) 2.9 x 10^-3
(d) 7.9 x 10^-2

17. For the reversible reaction,

The equilibrium shifts in forward direction (2014)
(a) by increasing the concentration of NH_3(g)
(b) by decreasing the pressure
(c) by decreasing the concentrations of N_2(g) and H_2(g)
(d) by increasing pressure and decreasing temperature.

18. For a given exothermic reaction, K_p and K’_p are the equilibrium constants at temperatures T1 and T2, respectively. Assuming that heat of reaction is constant in temperature range between T1 and T2, it is readily observed that (2014)
(a) K_p > K’_p
(b) K_p < K’_p
(c) K_p = K’_p
(d) K_p=1/K’_p

19. KMn0₄ can be prepared from K₂Mn0₄ as per the reaction,

The reaction can go to completion by removing OH^– ions by adding (NEET 2013)
(a) C0₂
(b) S0₂
(c) HCl
(d) KOH

20. Which of these is least likely to act as a Lewis base? (NEET 2013)
(a) BF₃
(b) PF₃
(c) CO
(d) F ^–

21. Accumulation of lactic acid (HC₃H₅0₃), a monobasic acid in tissues leads to pain and a feeling of fatigue. In a 0.10 M aqueous solution, lactic acid is 3.7% dissociates. The value of dissociation constant, K_a, for this acid will be (Karnataka NEET 2013)
(a) 1.4 x 10^-5
(b) 1.4 x 10^-4
(c) 3.7 x 10^-4
(d) 2.8 x 10^-4

22. At 100°C the K_w of water is 55 times its value at 25°C. What will be the pH of neutral solution? (log 55 = 1.74) (Karnataka NEET 2013)
(a) 7.00
(b) 7.87
(c) 5.13
(d) 6.13

23. The values of K_sp of CaC0₃ and CaC₂0₄ are 4.7 x 10^-9 and 1.3 x 10^-9 respectively at 25°C. If the mixture of these two is washed with water, what is the concentration of Ca²⁺ ions in water? (Karnataka NEET 2013)
(a) 5.831 x 10^-5 M
(b) 6.856 x 10^-5 M
(c) 3.606 x 10^-5 M
(d) 7.746 x 10^-5 M

24. The dissociation constant of a weak acid is 1 x 10^-4. In order to prepare a buffer solution with a pH = 5, the [Salt]/[Acid] ratio should be (Karnataka NEET 2013)
(a) 4:5
(b) 10 : 1
(c) 5 : 4
(d) 1 : 10

25. pH of a saturated solution of Ba(OH)₂ is 12. The value of solubility product (K_sp) of Ba(OH)₂ is (2012)
(a) 3.3 x 10^-7
(b) 5.0 x 10^-7
(c) 4.0 x 10^-6
(d) 5.0 x 10^-6

26. Equimolar solutions of the following substances were prepared separately. Which one of these will record the highest pH value? (2012)
(a) BaCl₂
(b) AlCl₃,
(c) LiCl
(d) BeCl₂

27.Buffer solutions have constant acidity and alkalinity because (2012)
(a) these give unionised acid or base on reaction with added acid or alkali
(b) acids and alkalies in these solutions are shielded from attack by other ions
(c) they have large excess of H⁺ or OH^– ions
(d) they have fixed value of pH.

28.Given that the equilibrium constant for the reaction,

has a value of 278 at a particular temperature. What is the value of the equilibrium constant for the following reaction at the same temperature? (Mains 2012)
 
(a) 1.8 x 10^-3 
(b) 3.6 x 10^-3 
(c) 6.0 x 10^-2
(d) 1.3 x 10^-5

29. Given the reaction between 2 gases represented by A₂ and B₂ to give the compound 

At equilibrium, the concentration of A₂ = 3.0 x 10^-3 M,B₂=4.2 x 10^-3 M _, AB = 2.8 x 10^-3 M If the reaction takes place in a sealed vessel at 527°C, then the value of K_c will be (Mains 2012)
(a) 2.0
(b) 1.9
(c) 0.62
(d) 4.5

30. The value of ΔH for the reaction 

 is less than zero. Formation of XY_4(g) will be favoured at (2011)
(a) high temperature and high pressure
(b) low pressure and low temperature
(c) high temperature and low pressure
(d) high pressure and low temperature

31. A buffer solution is prepared in which the concentration of NH₃ is 0.30 M and the concentration of NH₄⁺ is 0.20 M. If the equilibrium constant, K_b for NH₃ equals 1.8 x 10^-5, what is the pH of this solution? (log 2.7 = 0.43) (2011)
(a) 9.08
(b) 9.43
(c) 11.72
(d) 8.73

32. Which of the following is least likely to behave as Lewis base? (2011)
(a) H₂0
(b) NH₃
(C) BF₃
(d) OH^–

33. For the reaction, 

the equilibrium constant is K1 The equilibrium constant is K2 for the reaction,

34. In qualitative analysis, the metals of group 1 can be separated from other ions by precipitating them as chloride salts. A solution initially contains Ag⁺ and Pb²⁺ at a concentration of 0.10 M. Aqueous HCl is added to this solution until the Cl^– concentration is 0.10 M. What will the concentrations of Ag⁺ and Pb²⁺ be at equilibrium?
(K_sp for AgCl = 1.8 x 10^-10, K_sp for PbCl₂ = 1.7 x 10^-5) (Mains 2011)
(a) [Ag⁺] = 1.8 x 10^-7 M, [Pb²⁺] = 1.7 x 10^-6 M
(b) [Ag⁺] = 1.8 x 10^-11 M, [Pb²⁺] = 8.5 x 10^-5 M
(c) [Ag⁺] = 1.8 x 10^-9 M, [Pb²⁺] = 1.7 x 10^-3 M
(d) [Ag⁺] = 1.8 x 10^-11 M, [Pb²⁺] = 1.7 x 10^-4 M

35. If pH of a saturated solution of Ba(OH)₂ is 12, the value of its K_sp is (2010)
(a) 4.00 x 10^-6 M³
(b) 4.00 x 10^-7 M³
(c) 5.00 x 10^-6 M³
(d) 5.00 x 10^-7 M³

36. What is [H⁺] in mol/L of a solution that is 0.20 M in CH₃COONa and 0.10 M in CH₃COOH? Ka for CH₃COOH = 1.8 x 10^-5 (2010)
(a) 3.5 x 10^-4
(b) 1.1 x 10^-5
(c) 1.8 x 10^-5
(d) 9.0 x 10^-6

37. In which of the following equilibrium Kc and Kp are not equal? (2010)

38. In a buffer solution containing equal concentration of B^– and HB, the K_b for B^– is 10^-10. The pH of buffer solution is (2010)
(a) 10
(b) 7
(c) 6
(d) 4

39. The reaction,

is begun with the concentrations of A and B both at an initial value of 1.00 M. When equilibrium is reached, the concentration of D is measured and found to be 0.25 M. The value for the equilibrium constant for this reaction is given by the expression (Mains 2010)
(a) [(0.75)³(0.25)] ÷ [(1.00)²(1.00)]
(b) [(0.75)³(0.25)] ÷ [(0.50)²(0.75)]
(c) [(0.75)³(0.25)] ÷ [(0.50)²(0.25)]
(d) [(0.75)³(0.25)] ÷ [(0.75)²(0.25)]

40. The dissociation constants for acetic acid and HCN at 25°C are 1.5 x 10^-5 and 4.5 x 10^-10 respectively. The equilibrium constant for the equilibrium

would be (2009)
(a) 3.0 x 10^-5
(b) 3.0 x 10^-4
(c) 3.0 x 10⁴
(d) 3.0 x 10⁵

41. Which of the following molecules acts as a Lewis acid? (2009)
(a) (CH₃)₂0
(b) (CH₃)₃P
(c) (CH₃)₃N
(d) (CH₃) B

42. The ionization constant of ammonium hydroxide is 1.77 x 10^-5 at 298 K. Hydrolysis constant of ammonium chloride is (2009)
(a) 6.50 x 10^-12
(b) 5.65 x 10^-13
(c) 5.65 x 10^-12
(d) 5.65 x 10^-10

43. What is the OH^– in the final solution prepared by mixing 20.0 mL of 0.050 M HCl with 30.0 mL of 0.10 M Ba(OH)₂? (2009)
(a) 0.40 M
(b) 0.0050 M
(c) 0.12 M
(d) 0.10 M

44. The dissociation equilibrium of a gas AB₂ can be represented as :

The degree of dissociation is x and is small compared to 1. The expression relating the degree of dissociation (x) with equilibrium constant K_p and total pressure P is (2008)
(a) (2K_p/P)½
(b) (K_p/P)
(c) (2K_p/P)
(d) (2K_p/P)^1/3

45. If the concentration of OH^– ions in the reaction

is decreased by 1/4 times, then equilibrium concentration of Fe³⁺ will increase by (2008)
(a) 64 times
(b) 4 times
(c) 8 times
(d) 16 times

46. Equal volumes of three acid solutions of pH 3, 4 and 5 are mixed in a vessel. What will be the H⁺ ion concentration in the mixture? (2008)
(a) 3.7 x 10^-3 M
(b) 1.11 x 10^-3 M
(c) 1.11 x 10^-4 M
(d) 3.7 x 10^-4 M

47. The value of equilibrium constant of the reaction

is 8.0. The equilibrium constant of the reaction

will be (2008)
(a) 16
(b) 1/8
(c) 1/16
(d) 1/64

48. The values of for the reactions,

are in the ratio 9 : 1. If degree of dissociation of X and A be equal, then total pressure at equilibrium (i) and (ii) are in the ratio (2008)
(a) 36:1
(b) 1 : 1
(c) 3 : 1
(d) 1 : 9

49. A weak acid, HA, has a Ka of 1.00 x 10^-5. If 0.100 mol of this acid is dissolved in one litre of water, the percentage of acid dissociated at equilibrium is closest to (2007)
(a) 1.00%
(b) 99.9%
(c) 0.100%
(d) 99.0%

50. Calculate the pOH of a solution at 25°C that contains 1 x 10^-10 M of hydronium ions, i.e. H₃0⁺. (2007)
(a) 4.000
(b) 9.000
(c) 1.000
(d) 7.000

51. For the reaction:

ΔH_r =-170.8 KJ mol^-1
Which of the following statements is not true? (2006)
(a)The reaction is exothermic.
(b)At equilibrium, the concentrations of CO_2(g) and H₂0_(l) are not equal.
(c)The equilibrium constant for the reaction is given by K_p = [CO₂]/[CH₄][O₂]
(d)Addition of CH_4(g) or 0_2(g) at equilibrium will cause a shift to the right.

52. Which ofthe following pairs constitutes a buffer? (2006)
(a) HCl and KCl
(b) HN0₂ and NaN0₂
(c) NaOH and NaCl
(d) HN0₃ and NH₄N0₃

53. The hydrogen ion concentration of a 10^-8 M HCl aqueous solution at 298 K (K_w = 10^-14) is (2006)
(a) 1.0 x 10^-8 M
(b) 1.0 x 10^-6 M
(c) 1.0525 x 10^-7M
(d) 9.525 x 10^-8 M

54. At 25°C, the dissociation constant of a base, BOH, is 1.0 x 10^-12. The concentration of hydroxyl ions in 0.01 M aqueous solution of the base would be (2005)
(a) 1.0 x 10^-5 mol L^-1
(b) 1.0x 10^-6 mol L^-1
(c) 2.0 x 10^-6 mol L^-1
(d) 1.0 x 10^-7 mol L^-1

55. H₂S gas when passed through a solution of cations containing HCl precipitates the cations of second group of qualitative analysis but not those belonging to the fourth group. It is because (2005)
(a) presence of HCl decreases the sulphide ion concentration
(b) solubility product of group II sulphides is more than that of group IV sulphides
(c) presence of HCl increases the sulphide ion concentration
(d) sulphides of group IV cations are unstable in HCl.

56. Equilibrium constants K₁ and K₂ for the following equilibria: (2005)

(a) K₂ = 1 / K₁²
(b) K₂ = K₁²
(c) K₂ = 1 /K₁
(d) K₂ = K_{1 /}2

57. The solubility product of a sparingly soluble salt AX₂ is 3.2 x 10^-11. Its solubility (in moles/L) is (2004)
(a) 5.6 x 10^-6
(b) 3.1 x 10^-4
(c) 2 x 10^-4
(d) 4 x 10^-4

58. The rapid change of pH near the stoichiometric point of an acid-base titration is the basis of indicator detection. pH of the solution is related to ratio of the concentrations of the conjugate acid (HIn) and base (In ^– ) forms of the indicator by the expression (2004)

59. In Haber process 30 litres of dihydrogen and 30 litres of dinitrogen were taken for reaction which yielded only 50 % of the expected product. What will be the composition of gaseous mixture under the aforesaid condition in the end? (2003)
(a) 20 litres ammonia, 20 litres nitrogen, 20 litres hydrogen
(b) 10 litres ammonia, 25 litres nitrogen, 15 litres hydrogen
(c) 20 litres ammonia, 10 litres nitrogen, 30 litres hydrogen
(d) 20 litres ammonia, 25 litres nitrogen, 15 litres hydrogen

60. The reaction quotient (Q) for the reaction (2003)

(a) Q = K_c
(b) Q< K_c
(c) Q> K_c
(d) Q = 0
where K_c is the equilibrium constant.

61. Which one of the following statements is not true? (2003)
(a) Among halide ions, iodide is the most powerful reducing agent.
(b) Fluorine is the only halogen that does not show a variable oxidation state.
(c) HOCl is a stronger acid than HOBr.
(d) HF is a stronger acid than HCl.

62. The solubility product of Agl at 25°C is 1.0 x 10^-16 mol² L^-2. The solubility of Agl in 10^-4 N solution of KI at 25°C is approximately (in mol L^-1) (2003)
(a) 1.0 x 10^-16
(b) 1.0 x 10^-12
(c) 1.0 x 10^-10
(d) 1.0 x 10^-8

63. Reaction

In equilibrium condition, pressure of 0₂ depends on (2002)
(a) increase mass of Ba0₂
(b) increase mass of BaO
(c) increase temperature on equilibrium
(d) increase mass of Ba0₂ and BaO both.

64. Solubility of MX₂ type electrolytes is 0.5 x 10^-4 mole/lit., then find out K_sp of electrolytes, (2002)
(a) 5 x 10^-12
(b) 25 x 10^-10
(c) 1 x 10^-13
(d) 5 x 10^-13

65. Which has highest pH? (2002)
(a) CH₃COOK
(b) Na₂C0₃
(c) NH₄Cl
(d) NaN0₃

66. Solution of 0.1 N NH₄OH and 0.1 N NH4C1 has pH 9.25. Then find out pK_b of NH₄OH. (2002)
(a) 9.25
(b) 4.75
(c) 3.75
(d) 8.25

67. In HS^– , I^–, R – NH₂, NH₃ order of proton accepting tendency will be (2001)
(a) I ^– > NH₃ > R – NH₂ > HS^–
(b) NH₃ > R-NH₂ > HS > I ^–
(c) R – NH₂ > NH₃ > HS- > I ^–
(d) HS ^– > R – NH₂ > NH₃ > I ^–

68. Ionisation constant of CH₃COOH is 1.7 x 10^-5 and concentration of H⁺ ions is 3.4 x 10^-4. Then find out initial concentration of CH₃COOH molecules. (2001)
(a) 3.4 x 10^-4
(b) 3.4 x 10^-3
(c) 6.8 x 10^-4
(d) 6.8 x 10^-3

69. Solubility of M₂S salt is 3.5 x 10^-6 then find out solubility product. (2001)
(a) 1.7 x 10^-6
(b) 1.7 x 10^-16
(c) 1.7 x 10^-18
(d) 1.7 x 10^-12

70. Correct relation between dissociation constants of a dibasic acid is (2000)
(a) K_a1=K_a2
(b) K_a1>K_a2
(c) K_a1< K_a2
(d) K_a1 = 1/K_a2

71. For any reversible reaction, if we increase concentration of the reactants, then effect on equilibrium constant (2000)
(a) depends on amount of concentration
(b) unchange
(c) decrease
(d) increase.

72. Conjugate acid of NH₂– is (2000)
(a) NH₄OH
b) NH₄⁺
(c) NH₂^–
(d) NH₃

73. Which statement is wrong about pH and H⁺? (2000)
(a) pH of neutral water is not zero.
(b) Adding 1 N solution of CH₃COOH and 1 N solution of NaOH, pH will be seven.
(c) [H⁺] of dilute and hot H₂S0₄ is more than concentrated and cold H₂S0₄.
(d) Mixing solution of CH₃COOH and HCl, pH will be less than 7.

74. Equilibrium constant K_p for following reaction  (2000)

75. The strongest conjugate base is (1999)
(a)SO₄^2-
(b)Cl^–
(c)NO₃^–
(d)CH₃COO^–

76. The concentration of [H⁺] and concentration of [OH^–] of a 0.1 aqueous solution of 2% ionised weak acid is [ionic product of water = 1 x 10^-14] (1999)
(a) 2 x 10^-3 M and 5 x 10^-12 M
(b) 1 x 10^-3 M and 3 x 10^-11 M
(c) 0.02 x 10^-3 M and 5 x 10^-11 M
(d) 3 x 10^-2 M and 4 x 10^-13 M

77. The solubility of a saturated solution of calcium fluoride is 2 x 10^-4 moles per litre. Its solubility product is (1999)
(a) 22 x 10^-11
(b) 14 x 10^-4
(c) 2 x 10^-2
(d) 32 x 10^-12

78. If K1 and K2 are the respective equilibrium constants for the two reactions,
XeF_6(g) + H₂0_(g) —> XeOF_4(g) + 2HF_(g) 
Xe0_4(g) + XeF_6(g) —> XeOF_4(g) + Xe0₃F_2(g), the equilibrium constant of the reaction,
XeO_4(g) + 2HF_(g) —> Xe0₃F_2(g) + H₂0_(g) will be (1998)
(a) K₁/K2
(b) K1 . K2
(c) K1/(K2)²
(d) K2/K1

79. A physician wishes to prepare a buffer solution at pH = 3.85 that efficiently resists changes in pH yet contains only small concentration of the buffering agents. Which of the following weak acids together with its sodium salt would be best to uSe? (1997)
(a) 2, 5-Dihydroxy benzoic acid (pKa = 2.97)
(b) Acetoacetic acid (pKa = 3.58)
(c) m-Chlorobenzoic acid (pKa = 3.98)
(d) p-Chlorocinnamic acid (pKa = 4.41)

80. The hydride ion H^– is stronger base than its hydroxide ion OH^–. Which of the following reaction will occur if sodium hydride (NaH) is dissolved in water? (1997)
(a) H^– + H20 —> no reaction
(b) H^– (aq)+ H20 –> H2O
(c) H^– (aq) + H2O(l) –>OH^– + H2
(d) None of these.

81. The solubility product of CuS, Ag2S and HgS are 10^-31, 10^-44 and 10^-54 respectively. The solubilities of these sulphides are in the order (1997)
(a) HgS > Ag2S > CuS
(b) CuS > Ag2S > HgS
(c) Ag2S > CuS > HgS
(d) AgS > HgS > CuS

82. The equilibrium constant for the reaction

is K, then the equilibrium constant for the equilibrium

is (1996)
(a) √K
(b) √1/K
(c) 1/K
(d)1/K²

83. The ionic product of water at 25°C is 10^-14. Its ionic product at 90°C will be, (1996)
(a) 1 x 10^-14
(b) 1 x 10^-16
(c) 1 x 10^-20
(d) 1 x 10^-12

84. If α is dissociation constant, then the total number of moles for the reaction,2HI —» H₂ + I₂ will be (1996)
(a) 1
(b) 1- α
(c) 2
(d) 2 – α

85. The pH value of N/10 NaOH solution is (1996)
(a) 12
(b) 13
(c) 10
(d) 11

86. Which of the following is not a Lewis acid? (1996)
(a) SiF₄
(b) C₂H₄
(C) BF₃
(d) FeCl₃

87. The pH value of blood does not appreciably change by a small addition of an acid or a base, because the blood (1995)
(a) can be easily coagulated
(b) contains iron as a part of the molecule
(c) is a body fluid
(d) contains serum protein which acts as buffer.

88. The pH value of a 10 M solution of HCl is (1995)
(a) equal to 1
(b) equal to 2
(c) less than 0
(d) equal to 0

89. The solubility of AgCl will be minimum in (1995)
(a) 0.01 M CaCl₂
(b) pure water
(c) 0.001 M AgN0₃
(d) O.Ol M NaCl

90. In liquid-gas equilibrium, the pressure of vapours above the liquid is constant at (1995)
(a) constant temperature
(b) low temperature
(c) high temperature
(d) none of these.

91. Which one of the following is most soluble?
(a) Bi₂S₃ (Ksp = 1 x10^-70)
(b) Ag₂S (Ksp = 6 x 10^-51)
(c) CuS (Ksp = 8 x 10^-37)
(d) MnS (Ksp = 1 x 10^-16)

92. At 80°C, distilled water has [H30⁺] concentration equal to 1 x 10^-6 mole/litre. The value of Kw at this temperature will be (1994)
(a) 1 x 10^-12
(b) 1 x 10^-15
(c) 1 x 10^-6
(d) 1 x 10^-9

93. According to Le Chatelier’s principle, adding heat to a solid and liquid in equilibrium will cause the (1993)
(a) temperature to increase
(b) temperature to decrease
(c) amount of liquid to decrease
(d) amount of solid to decrease.

94. 0.1 M solution of which one of these substances will act basic? (1992)
(a) Sodium borate
(b) Ammonium chloride
(c) Calcium nitrate
(d) Sodium sulphate

95. Which one of the following information can be obtained on the basis of Le Chatelier principle? (1992)
(a) Dissociation constant of a weak acid
(b) Entropy change in a reaction
(c) Equilibrium constant of a chemical reaction
(d) Shift in equilibrium position on changing value of a constraint.

96. Aqueous solution of acetic acid contains (1991)
(a) CH₃COO^– and H⁺
(b) CH₃COO^– , H₃0⁺ and CH₃COOH
(c) CH₃COO^–, H₃0⁺ and H⁺
(d) CH₃COOH, CH₃COO^– and H⁺

97. K1 and K2 are equilibrium constant for reactions (i) and (ii) (1989)

(a) K1=[1/K₂]²
(b) K1= K_2²
(c) K1=1/K₂
(d) K1= (K₂)°

98. The compound whose water solution has the highest pH is (1988)
(a) NaCl
(b) NaHC0₃
(c) Na₂C0₃
(d) NH₄CI

Answer Key

Explanations

NEET AIPMT Chemistry Chapter Wise Solutions – Thermodynamics

NEET AIPMT Chemistry Chapter Wise SolutionsPhysicsBiology

1.For a given reaction, ΔH = 35.5 kJ mol^-1 and ΔS = 83.6 J K^-1 mol^-1 . The reaction is spontaneous at (Assume that ΔH and ΔS do not vary with temperature.) (NEET 2017)
(a) T > 425 K
(b) all temperatures
(c) T> 298 K
(d) T<425 K

2.A gas is allowed to expand in a well insulated container against a constant external pressure of 2.5 atm from an initial volume of 2.50 L to a final volume of 4.50 L. The change in internal energy ΔU of the gas in joules will be (NEET 2017)
(a) -500 J
(b) -505 J
(c) +505 J
(d) 1136.25 J

3.For a sample of perfect gas when its pressure is changed isothermally from p_i to p_f the entropy change is given by  (NEET II 2016)

4.The correct thermodynamic conditions for the spontaneous reaction at all temperatures is (NEET-I 2016)
(a) ΔH < 0 and ΔS > 0
(b) ΔH < 0 and ΔS < 0
(c) ΔH < 0 and ΔS = 0
(d) ΔH > 0 and ΔS < 0

5.Consider the following liquid-vapour equilibrium. (NEET-I 2016)

6.The heat of combustion of carbon to C0₂ is -393.5 kJ/mol. The heat released upon  formation of 35.2 g of C0₂ from carbon and oxygen gas is (2015)
(a)+315 kJ
(b) – 630 kJ
(c) – 3.15 kJ
(d) – 315 kJ

7. Which of the following statements is correct i for the spontaneous adsorption of a gas? (2014)
(a) ΔS is negative and, therefore ΔH should be highly positive.
(b) ΔS is negative and therefore, ΔH should be highly negative.
(c) ΔS is positive and therefore, ΔH should be negative.
(d) ΔS is positive and therefore, ΔH should also be highly positive.

8. For the reaction, X₂0_4(l) —> 2X0_2(g)
ΔU = 2.1 kcal, ΔS = 20 cal K^-1 at 300 K Hence, ΔG is (2014)
(a) 2.7 kcal
(b) – 2.7 kcal
(c) 9.3 kcal
(d) – 9.3 kcal

9. A reaction having equal energies of activation | for forward and reverse reactions has (NEET 2013)
(a) ΔH = 0
(b)ΔH = ΔG=ΔS=0
(c) ΔS = 0
(d) ΔG = 0

10. When 5 litres of a gas mixture of methane and propane is perfectly combusted at 0°C and 1 atmosphere, 16 litres of oxygen at the same temperature and pressure is consumed. The amount of heat released from this combustion in kJ (ΔH_comb (CH₄) = 890 kJ mol^-1, ΔH_comb (C₃H₈) = 2220 kJ mol^-1) is (Karnataka NEET 2013)
(a) 38
(b) 317
(c) 477
(d) 32

11.Three thermochemical equations are given below 
(i) C(graphite) + 0_2(g) —>CO_2(g) ;ΔH° = x kJ moL^-1
(ii) C(graphite)+ ½ 0_2(g) —> CO_(g) ;ΔH° = y kJ moL^-1
(iii) CO(g) + ½ 0_2(g) —>CO_2(g) ; ΔH°=z kJ moL^-1
Based on the above equations, find out which of the relationship given below is correct, (Karnataka NEET 2013)
(a) z = x + y
(b) x = y + z
(c) y = 2z – x
(d) x = y – z

12. In which of the following reactions, standard reaction entropy change (ΔS°) is positive and standard Gibb’s energy change (ΔG°) decreases sharply with increasing temperature? (2012)
(a) C(graphite) + ½ 0_2(g) —>CO(g)
(b) CO(g) + ½ 0_2(g) —> C0_2(g)
(c) Mg_(s)+ ½ 0_2(g)—> MgO_(s)
(d) 1/2 C(graphite) + ½ 0_2(g)—> ½ CO_2(g)

13. The enthalpy of fusion of water is 1.43 5 kcal/mol. The molar entropy change for the melting of ice at 0°C is (2012)
(a) 10.52 cal/(mol K)
(b) 21.04 cal/(mol K)
(c) 5.260 cal/(mol K)
(d) 0.526 cal/(mol K)

14. Standard enthalpy of vaporisation Δ_vapH° for water at 100°C is 40.66 kJ mol^-1. The internal energy of vaporisation of water at 100°C (in kJ mol^-1) is (2012)
(a) +37.56
(b) -43.76
(c) +43.76
(d) +40.66
(Assume water vapour to behave like an ideal gas)

15. If the enthalpy change for the transition of liquid water to steam is 30 kJ mol^-1 at 27°C, the entropy change for the process would be (2011)
(a) 10 J mol^-1 K^-1
(b) 1.0 J mol^-1 K^-1
(c) 0.1 J mol^-1 K^-1
(d) 100 J mol^-1 K^-1

16. Enthalpy change for the reaction, 4H_(g) —> 2H_2(g) is —869.6 kJ The dissociation energy of H – H bond is (2011)
(a) – 434.8 kJ
(b) – 869.6 kJ
(c) + 434.8 kJ
(d) + 217.4 kJ

17. Which of the following is correct option for free expansion of an ideal gas under adiabatic . condition? (2011)
(a) q = 0, ΔT + 0, w = 0
(b) q ≠ 0, ΔT = 0, w = 0
(c) q = 0, ΔT = 0, w = 0
(d) q = 0, ΔT<0, w≠0

18.Consider the following processes: (Mains 2011)
ΔH (kJ/mol) 
1/2A—>B           +150
3B —>2C + D      -125
E + A —> 2D      +350
For B + D —> E + 2C, AH will be
(a) 525 kJ/mol
(b) -175 kJ/mol
(c) -325 kJ/mol
(d) 325 kJ/mol

19. For an endothermic reaction, energy of activation is E_a and enthalpy of reaction is ΔH (both of these in kJ/mol). Minimum value of E_a will be (2010)
(a) less than ΔH
(b) equal to ΔH
(c) more than ΔH
(d) equal to zero

20. Standard entropies of X₂, Y₂ and XY₃ are 60, 40 and 50 J K^-1 mol^-1 respectively. For the reaction 1/2X₂+ 3/2Y₂= XY₃, ΔH =-30 kJ, to be at equilibrium, the temperature should be (2010)
(a) 750 K
(b) 1000K
(c) 1250 K
(d) 500 K

21.Match List I (Equations) with List II (Type of processes) and select the correct option. (Mains 2010)

(a) A – (i), B – (ii), C – (iii), D – (iv)
(b) A – (iii), B – (iv), C – (ii), D – (i)
(c) A – (iv), B – (i), C – (ii), D – (iii)
(d) A – (ii), B – (i), C – (iv), D – (iii)

22.Three moles of an ideal gas expanded spontaneously into vacuum. The work done will be (Mains 2010)
(a) infinite
(b) 3 Joules
(c) 9 Joules
(d) zero

23. For vaporization of water at 1 atmospheric pressure, the values of ΔH and ΔS are 40.63 kJ mol^-1 and 108.8 J K^-1 mol^-1, respectively. The temperature when Gibb’s energy change ( ΔG) for this transformation will be zero, is (Mains 2010)
(a) 273.4 K
(b) 393.4 K
(c) 373.4 K
(d) 293.4 K

24.The following two reactions are known
Fe₂O_3(s) + 3CO_(g)—> 2Fe_(s)+ 3C0_{2(g) ;}
ΔH= -26.8 kJ 
FeO_(s) + CO—> Fe+ C0_{2(g) ;}
ΔH=-16.5 kJ
The value of AH for the following reaction
Fe₂O_3(s) + CO_(g)—-> 2FeO_(s) + C0_2(g) is (Mains 2010)
(a) + 10.3 kJ
(c) – 10.3 kJ
(b) – 43.3 kJ
(d) + 6.2 kJ

25. The values of ΔH and ΔS for the reaction,C(graphite) + C0_2(g) —> 2CO_(g) are 170 kJ and 170 J K^-1, respectively. This reaction will be spontaneous at (2009)
(a) 910 K
(b) 1110K
(c) 510 K
(d) 710 K

26. From the following bond energies: (2009)

(a) – 243.6 kJ mol^-1
(c) 553.0 kJ mol^-1
(b) – 120.0 kJ mol^-1
(d) 1523.6 kJ mol^-1

27. Bond dissociation enthalpy of H₂, Cl₂ and HCl are 434, 242 and 431 kJ mol^-1 respectively. Enthalpy of formation of HCl is (2008)
(a) -93 kJ mol^-1
(b) 245 kJ mol^-1
(c) 93 kJ mol^-1
(d) -245 kJ mol^-1

28. For the gas phase reaction,
PCl_5(g) =PCl _3(g)+ Cl_2(g)
which of the following conditions are correct? (2008)
(a) ΔH < 0 and ΔS < 0
(b) ΔH > 0 and ΔS < 0
(c) ΔH = 0 and ΔS < 0
(d) ΔH > 0 and ΔS > 0

29. Which of the following are not state functions?  (2008)
(I) q + w
(II) q
(III) w
(IV) H – TS
(a) (I), (II) and (III)
(b) (II) and (III)
(c) (I) and (IV)
(d) (II), (III) and (IV)

30. Consider the following reactions:

Enthalpy of formation of H₂O_(l) is (2007)
(a) +X₃ kJ mol^-1
(b) -X₄ kJ mol^-1
(c) +X₁ kJ mol^-1
(d) -X₂ kJ mol^-1

31. Given that bond energies of H – H and Cl – Cl are 430 kJ mol^-1 and 240 kJ mol^-1 respectively and ΔHf for HCl is -90 kJ mol^-1, bond enthalpy of HCl is (2007)
(a) 380 kJ mol^-1
(b) 425 kJ mol^-1
(c) 245 kJ mol^-1
(d) 290 kJ mol^-1

32. Identify the correct statement for change of Gibb’s energy for a system (ΔG system) at constant temperature and pressure. (2006)
(a) If ΔG system < 0, the process is not spontaneous.
(b) If ΔG system > 0, the process is spontaneous.
(c) If ΔG system = 0, the system has attained equilibrium.
(d) If ΔG system, = 0, the system is still moving in a particular direction.

33. Assume each reaction is carried out in an open container. For which reaction will ΔH = ΔE ?(2006)

34. The enthalpy and entropy change for the reaction:
Br_2(l) + Cl_2(g) —>2BrCl_(g)
are 30 kJ mol^-1 and 105 J K^-1 mol^-1 respectively. The temperature at which the reaction will be in equilibrium is (2006)
(a) 300 K
(b) 285.7 K
(c) 273 K
d) 450 K

35. The enthalpy of hydrogenation of cyclohexene is -119.5 kJ mol^-1. If resonance energy of benzene is -150.4 kJ mol^-1, its enthalpy of hydrogenation would be (2006)
(a) – 358.5 kJ mol^-1
(b) – 508.9 kJ mol^-1
(c) – 208.1 kJ mol^-1
(d) – 269.9 kJ mol^-1

36. Which of the following pairs of a chemical reaction is certain to result in a spontaneous reaction? (2005)
(a) Exothermic and increasing disorder
(b) Exothermic and decreasing disorder
(c) Endothermic and increasing disorder
(d) Endothermic and decreasing disorder

37. A reaction occurs spontaneously if (2005)
(a) TΔS < ΔH and both ΔH and ΔS are +ve
(b) TΔS > ΔH and ΔH is +ve and ΔS is -ve
(c) TΔS > ΔH and both ΔH and ΔS are +ve
(d) TΔS = ΔH and both ΔH and ΔS are +ve

38. The absolute enthalpy of neutralisation of the reaction:. (2005)
MgO_(s) + 2HCl_(aq) —> MgCl_2(aq) + H₂0_(l) will be
(a) -57.33 kJ mol ^-1
(b) greater than -57.33 kJ mol^-1
(c) less than -57.33 kJ mol^-1
(d) 57.33 kJ mol^–1

39. If the bond energies of H-H, Br-Br, and H-Br are 433,192 and 364 kJ mol^-1 respectively, the ΔH° for the reaction H_2(g) + Br_2(g) —> 2HBr_(g) is (2004)
(a) -261 kJ
(b) +103 kJ
(c) +261 kJ
(d) -103 kJ

40. Standard enthalpy and standard entropy changes for the oxidation of ammonia at 298 K are -382.64 kJ mol^-1 and -145.6 kJ mol^-1, respectively. Standard Gibb’s energy change for the same reaction at 298 K is (2004)
(a) – 221.1 kJ mol^-1
(b) – 339.3 kJ mol^-1
(c) – 439.3 kJ mol^-1
(d) – 523.2 kJ mol^-1

41. Considering entropy (S) as a thermodynamic parameter, the criterion for the spontaneity of any process is (2004)
(a) ΔS System+ ΔS surroundings > 0
(b) ΔS System — ΔS surroundings > 0
(c) ΔS system > 0 only
(d) ΔS surroundings > 0 only.

42. The work done during the expansion of a gas from a volume of 4 dm³ to 6 dm³ against a constant external pressure of 3 atm is (1 L atm = 101.32 J) (2004)
(a) – 6 J
(b) – 608 J
(c) + 304 J
(d) – 304 J

43. For the reaction,
C₂H_8(g) + 50_2(g) —> 3C0_2(g) + 4H₂0_(l) 
at constant temperature,ΔH – ΔE is (2003)
(a) +RT
(b) -3RT
(c) +3RT
(d)-RT

44. The densities of graphite and diamond at 298 K are 2.25 and 3.31 g Cm^-3, respectively. If the standard free energy difference (ΔG°) is equal to 1895 J mol^-1, the pressure at which graphite will be transformed into diamond at 298 K is (2003)
(a) 9.92 x 10⁸ Pa
(b) 9.92 x 10⁷ Pa
(c) 9.92 x 10⁶ Pa
(d) 9.92 x 10⁵ Pa

45. What is the entropy change (in J K^-1 mol^-1) when one mole of ice is converted into water at 0°C? (The enthalpy change for the conversion of ice to liquid water is 6.0 kJ mol^-1 at 0°C.) (2003)
(a) 20.13
(b) 2.013
(c) 2.198
(d) 21.98

46. Formation of a solution from two components can be considered as
(i) Pure solvent —> separated solvent molecules, ΔH1
(ii) Pure solute —> separated solute molecules, ΔH2
(iii) Separated solvent and solute molecules —> solution, ΔH3
Solution so formed will be ideal if (2003)
(a)ΔH soln = ΔH1+ ΔH2 + ΔH3
(b)ΔH soln = ΔH1 + ΔH2 – ΔH3
(c) ΔH soln = ΔH1- ΔH2 – ΔH3
(d) ΔH soln = ΔH3- ΔH1 – ΔH2

47. For which one of the following equations is ΔHºreact equal to ΔH°f for the product? (2003)
(a) N_2(g) + O_3(g) —>N₂O_3(g)
(b) CH_4(g) + 2Cl_2(g) —> CH₂Cl_2(l)+ 2HCl_(g)
(c) Xe_(g) + 2F_2(g) —> XeF_4(g)
(d) 2CO_(g) + 0_2(g) —> 2C0_2(g)

48. The molar heat capacity of water at constant pressure, C , is 75 J K^-1 mol^-1. When 1.0 kJ of heat is supplied to 100 g of water which is free to expand, the increase in temperature of water is (2003)
(a) 1.2 K
(b) 2.4 K
(c) 4.8 K
(d) 6.6K

49. Unit of entropy is (2002)
(a) J K^-1 mol^-1
(b) J mol^-1
(c) J^-1 K^-1 mol^-1
(d) J K mol^-1

50. In a closed insulated container a liquid is stirred with a paddle to increase the temperature which of the following is true? (2002)
(a) ΔE=W≠0, q = 0
(b) ΔE = W = q ≠0
(c) ΔE = 0, W= q ≠ 0
(d) W=0, ΔE=q≠0.

51. Heat of combustion ΔH for C_(s), H_2(g) and CH_4(g) are -94, -68 and -213 kcal/mol, then ΔH for C_(s)+ 2H_2(g)-> CH_4(g) is (2002)
(a) -17 kcal
(b) -111 kcal
(c) -170 kcal
(d) -85 kcal

52. Which reaction is not feasible? (2002)
(a) 2KI + Br₂ —> 2KBr + I₂
(b) 2KBr + I₂ –>2KI + Br₂
(c) 2KBr + Cl₂ -> 2KCl + Br₂
(d) 2H₂0 + 2F₂ -> 4HF + O₂

53. 2 mole of ideal gas at 27°C temperature is expanded reversibly from 2 lit. to 20 lit. Find entropy change. (R = 2 cal/mol K) (2002)
(a) 92.1
(b)0
(c) 4
(d) 9.2

54. Change in enthalpy for reaction,
2H₂0_2(l) —> 2H₂0_(l) + 0_2(g)
if heat of formation of H₂0_2(l) and H₂0_(l) are -188 and -286 kJ/mol respectively, is (2001)
(a) -196 kJ/mol
(b) +196kJ/mol
(c) +948 kJ/mol
(d) -948 kJ/moie

55. When 1 mol of gas is heated at constant volume temperature is raised from 298 to 308 K. Heat supplied to the gas is 500 J. Then which statement is correct? (2001)
(a) q = w = 500 J,ΔE = 0
(b) q = ΔE = 500 J, w = 0
(c) q = w = 500 J, ΔE = 0
(d) ΔE = 0, q = w = -500 J

56. Enthalpy of CH₄+ 1/2 0₂ —> CH₃OH is negative. If enthalpy of combustion of CH₄ and CH₃OH are x and y respectively. Then which relation is correct? (2001)
(a) x> y
(b) x < y
(c) x=y
(d) x³y

57. Pb0₂ —> PbO; ΔG₂₉₈ <0
Sn0₂ —> SnO; AG₂₉₈> 0
Most probable oxidation state of Pb and Sn will be (2011)
(a) Pb⁴⁺, Sn⁴⁺
(b) Pb⁴⁺, Sn²⁺
(c) Pb²⁺, Sn²⁺
(d) Pb²⁺, Sn⁴⁺

58. Cell reaction is spontaneous when (2000)
(a) ΔG° is negative
(b) ΔG° is positive
(c) ΔE°red  is positive
(d) ΔE°red is negative.

59. 2Zn + 0₂ —> 2ZnO; ΔG° = -616 J
2Zn + S₂ —>+ 2ZnS; ΔG° = -293 J
S₂ + 20₂ —>+ 2S0₂; ΔG° = -408
ΔG° for the following reaction 2ZnS + 30₂ —> 2ZnO + 2S0₂ is (2000)
(a) -731 J
(b) -1317 J
(c) -501 J
(d) +731 J

60. At 27°C latent heat of fusion of a compound is 2930 J/mol. Entropy change is (2000)
(a) 9.77 J/mol-K
(b) 10.77 J/mol-K
(c) 9.07 J/mol-K
(d) 0.977 J/mol-K

61. For the reaction,
C₂H₅OH_(l) + 30_2(g) —> 2C0_2(g)+ 3H₂0_(l) which one is true (2000)
(a) ΔH = ΔE – RT
(b) ΔH = ΔE + RT
(c) ΔH = ΔE + 2RT
(d) ΔH = ΔE- 2RT

62. In an endothermic reaction, the value of ΔH is (1999)
(a) negative
(b) positive
(c) zero
(d) constant.

63. In the reaction: S + 3/2 0₂ —> S0₃ + 2x kcal and S0₂ + 1/2 0₂ —> S0₃ + y kcal, the heat of formation of S0₂ is (1999)
(a) (2x+y)
(b) (x – y)
(c)(x + y)
(d) (2x-y)

64. Identify the cojrect statement tegarding entropy. (1998)
(a) At absolute zero of temperature, the entropy of all crystalline substances is taken to be zero.
(b) At absolute zero of temperature, the entropy of a perfectly crystalline substance is +ve.
(c) At absolute zero of temperature, entropy of a perfectly crystalline substance is taken to be zero.
(d) At 0°C, the entropy of a perfectly crystalline substance is taken to be zero.

65. One mole of an ideal gas at 300 K is expanded isothermally from an initial volume of 1 litre to 10 litres. The ΔE for this process is (1998)
(R = 2 cal mol^-1K^-1)
(a) 1381.1 cal
(b) zero
(c) 163.7 cal
(d) 9Latm

66. Given that C + O₂ —> C0₂, ΔH° = – x kJ 2CO + 0₂ —> 2C0₂, ΔH° = -y kJThe enthalpy of formation of carbon monoxide will be y-2x (1997)
(a) y-2x/2
(b) 2x-y
(c) y – 2x
(d)2x-y/2

67. Which of the following is the correct equation? (1996)
(a) ΔU = ΔW+ ΔQ
(b) ΔU=ΔQ-W
(c) ΔW= ΔU + ΔQ
(d) None of these

68. If enthalpies of formation for C₂H_4(g), C0_2(g) and H₂0_(l) at 25°C and 1 atm pressure are 52, – 394 and – 286 kJ/mol respectively, then enthalpy of combustion of C₂H₄will be (1995)
(a) +141.2 kJ/mol
(b) +1412 kJ/mol
(c) – 141.2 kJ/mol
(d) – 1412 kJ/mol

69. A chemical reaction is catalyzed by a catalyst X. Hence X (1995)
(a) reduces enthalpy of the reaction
(b) does not affect equilibrium constant of reaction
(c) decreases rate constant of the reaction
(d) increases activation energy of the reaction.

70. Standard state Gibb’s free energy change for isomerization reaction cis-2-pentene = trans- 2-pentene is -3.67 kJ/mol at 400 K. If more trans-2-pentene is added to the reaction vessel, then (1995)
(a) equilibrium remains unaffected
(b) equilibrium is shifted in the forward direction
(c) more cis-2-pentene is formed
(d) additional trans-2-pentene is formed.

71. For a reaction to occur spontaneously (1995)
(a) ΔH must be negative
(b) ΔS must be negative
(c) (ΔH – TΔS) must be negative
(d) (ΔH + TΔS) must be negative.

72. During isothermal expansion of an ideal gas, its (1994, 91)
(a) internal energy increases
(b) enthalpy decreases
(c) enthalpy remains unaffected
(d) enthalpy reduces to zero.

73. Following reaction occurring in an automobile 2C₈H_18(g)+ 250_2(g)—» 16C0_2(g) + 18H₂0(g) The sign of ΔH, ΔS and ΔG would be (1994)
(a) -,+, +
(b) +, +, –
(c)+,-,+
(d) -, +, –

74. For the reaction N₂ + 3H₂ = 2NH₃, ΔH = ? (1991)
(a) ΔE + 2RT
(b) ΔE – 2RT
(c) ΔH = RT
(d) ΔE-RT

75. If ΔH is the change in enthalpy and ΔE, the change in internal energy accompanying a gaseous reaction, then (1990)
(a) ΔH is always greater than ΔE
(b) ΔH < ΔE only if the number of moles of the products is greater than the number of moles of the reactants
(c) ΔH is always less than ΔE
(d) ΔH < ΔE only if the number of moles of products is less than the number of moles of the reactants.

Answer Key

Explanations

NEET AIPMT Chemistry Chapter Wise Solutions – Solutions

NEET AIPMT Chemistry Chapter Wise SolutionsPhysicsBiology

1.If molality of the dilute solution is doubled, the value of molal depression constant (K_f) will be (NEET 2017)
(a) halved
(b) tripled
(c) unchanged
(d) doubled.

2.Which of the following is dependent on temperature? (NEET 2017)
(a) Molarity
(b) Mole fraction
(c) Weight percentage
(d) Molality

3.The van’t Hoff factor (i) for a dilute aqueous solution of the strong electrolyte barium hydroxide is (NEET-II 2016)
(a) 0
(b) 1
(c) 2
(d) 3

4.Which one of the following is incorrect for ideal solution?(NEET-II 2016)
(a)ΔH_mix=0
(b)ΔU_mix=0
(c)ΔP=P_obs-P=0
(d)ΔG_mix=0

5. Which of the following statements about the composition of the vapour over an ideal 1 : 1 molar mixture of benzene and toluene is correct? Assume that the temperature is constant at 25°C. (Given, vapour pressure data at 25°C, benzene = 12.8 kPa, toluene = 3.85 kPa)  (NEET-1 2016)
(a) The vapour will contain equal amounts of benzene and toluene.
(b) Not enough information is given to make a prediction.
(c) The vapour will contain a higher percentage of benzene.
(d) The vapour will contain a higher percentage of toluene.

6.At 100°C the vapour pressure of a solution of 6.5 g of a solute in 100 g water is 732 mm. If Kb = 0.52, the boiling point of this solution will be (NEET-1 2016)
(a) 102°C
(b) 103°C
(c) 101°C
(d) 100°C

7. What is the mole fraction of the solute in a 1.00 m aqueous solution? (2015, 2011)
(a) 1.770
(b) 0.0354
(c) 0.0177
(d) 0.177

8. The boiling point of 0.2 mol kg^-1 solution of  X in water is greater than equimolal solution of Y in water. Which one of the following statements is true in this case? (2015, Cancelled)
(a) Molecular mass of X is less than the molecular mass of Y.
(b) Y is undergoing dissociation in water while X undergoes no change.
(c) X is undergoing dissociation in water.
(d) Molecular mass of X is greater than the molecular mass of Y.

9. Which one of the fol lowing electrolytes has the same value of van’t Hoff factor (i) as that of Al₂(S0₄)₃ (if all are 100% ionised)?(2015, Cancelled)
(a) Al(N0₃)₃
(b) K₄Fe(CN)₆]
(c) K₂S0₄
(d) K₃[Fe(CN)₆]

10. Which of them is not equal to zero for an ideal solution? (2015, Cancelled)
(a) ΔV_mix
(b) ΔP = P_obs-P_Raoult
(c) ΔH_mix
(d)ΔS_mix

11. Of the following 0.10 m aqueous solutions, which one will exhibit the largest freezing point depression? (2014)
(a) KCl
(b) C₆H₁₂0₆
(c) Al₂(S0₄)₃
(d) K₂SO₄

12. How many grams of concentrated nitric acid solution should be used to prepare 250 mL of 2.0 M HN0₃? The concentrated acid is 70% HN0₃. (MEET 2013)
(a) 70.0 g cone. HN0₃
(b) 54.0 g cone. HN0₃
(c) 45.0 g cone. HN0₃
(d) 90.0 g cone. HN0₃

13. Which condition is not satisfied by an ideal ‘ solution? (Karnataka NEET 2013)
(a) Δ_mixV=0
(b) Δ_mixS=0
(c) Obeyance to Raoult’s Law
(d)Δ_mixH=0

14. pA and pB are the vapour pressure of pure liquid components, A and B, respectively of an ideal binary solution. If xA represents the mole fraction of component A, the total pressure of the solution will be (2012)
(a) pA + xA(pB-pA)
(b) pA+xA(pA-pB)
(c) pB + xA(pB – pA)
(d) pB+xA(pA-pB)

15. Vapour pressure of chloroform (CHCl₃) and dichloromethane (CH₂Cl₂) at 25°C are 200 mm Hg and 41.5 mm Hg respectively.  Vapour pressure of the solution obtained by mixing 25.5 g of CHCl₃ and 40 g of CH₂Cl₂ at the same temperature will be (Mains 2012)
(Molecular mass of CHCl₃ = 119.5 u and molecular mass of CH₂Cl₂ = 85 u)
(a) 173.9 mm Hg
(b) 615.0 mm Hg
(c) 347.9 mm Hg
(d) 285.5 mm Hg

16. The freezing point depression constant for  water is -1.86° C m^-1. If 5.00 g Na₂S0₄ is dissolved in 45.0 g H₂0, the freezing point is changed by -3.82°C. Calculate the van’t Hoff factor for Na₂S0₄. (2011)
(a) 2.05
(b) 2.63
(c) 3.11
(d) 0.381

17. The van’t Hoff factor i for a compound which undergoes dissociation in one solvent and association in other solvent is respectively (2011)
(a) less than one and greater than one
(b) less than one and less than one
(c) greater than one and less than one
(d) greater than one and greater than one.

18. A 0.1 molal aqueous solution of a weak acid is 30% ionized. If K_f for water is 1.86°C/m, the freezing point of the solution will be (Mains 2011)
(a) -0.18°C
(b) -0.54°C
(c) – 0.36°C
(d) – 0.24°C

19. 200 mL of an aqueous solution of a protein contains its 1.26 g. The osmotic pressure of this solution at 300 K is found to be 2.57 x 10^-3 bar. The molar mass of protein will be (R = 0.083 L bar mol^-1K^-1) (Mains 2011)
(a) 51022 g moL^-1
(b) 122044 g moL^-1
(c) 31011 g moL^-1
(d) 61038 g moL^-1

20. An aqueous solutionis 1.00 molal in KI. Which change will cause the vapour pressure of the solution to increase? (2010)
(a) Addition of NaCl
(b) Addition of Na₂S0₄
(c) Addition of 1.00 piolal KI
(d) Addition of water

21. A solution of sucrose (molar mass = 342 g mol^-1) has been prepared by dissolving 68.5 g of sucrose in 1000 g of water. The freezing point of the solution obtained will be (Kf for water = 1.86 K kg mol^-1) : (2010)
(a) -0.372°C
(b) -0.520°C
(c) + 0.372°C
(d) -0.570“C

22. A 0.0020 m aqueous solution of an ionic compound [Co(NH₃)₅(No₂)]Cl freezes at – 0.00732°C. Number of moles of ions which 1 mol of ionic compound produces on being dissolved in water will be (Kf=-1.86°C/m] (2009)
(a) 3
(b) 4
(c) 1
(d) 2

23. 0.5 molal aqueous solution of a weak acid (HX) is 20% ionized .If Kf for water is 1.86 K kg mol^-1, the lowering in freezing point of the solution is (2007)
(a) 0.56 K
(b) 1.12 K
(c) -0.56 K
(d) 1.12 K

24. Concentrated aqueous sulphuric acid is 98% H₂S0₄ by mass and has a density of 1.80 g mL^-1 Volume of acid required to make one litre of 0.1 M H₂S0₄ solution is (2007)
(a) 16.65 mL
(b) 22.20 mL
(c) 5.55 mL
(d) 11.10 mL

25. During osmosis, flow of water through a semipermeable membrane is (2006)
(a) from solution having lower concentration only
(b) from solution having higher concentration only
(c) from both sides of semipermeable membrane with equal flow rates
(d) from both sides of semipermeable membrane with unequal flow rates.

26. A solution of acetone in ethanol (2006)
(a) obeys Raoult’s law
(b) shows a negative deviation from Raoult’s law
(c) shows a positive deviation from Raoult’s law
(a) behaves like a near ideal solution.

27. 1.00 g of a non-electrolyte solute (molar mass 250 g mol^-1) was dissolved in 51.2 g of benzene. If the freezing point depression constant, Kf of benzene is 5.12 K kg mol^-1, the freezing point of benzene will be lowered by (2006)
(a) 0.2 K
(b) 0.4 K
(c) 0.3 K
(d) 0.5 K

28. A solution containing 10 g per dm³ of urea (molecular mass = 60 g mol^-1) is isotonic with a 5% solution of a nonvolatile solute is (2006)
(a) 200 g mol^-1
(b) 250 g mol^-1
(c) 300 g mol^-1
(d) 350 g mol^-1

29. The mole fraction of the solute in one molal aqueous solution is (2005)
(a) 0.009
(b) 0.018
(c) 0.027
(d) 0.036

30. The vapour pressure of two liquids P and Q are 80 and 60 torr, respectively. The total vapour pressure of solution obtained by mixing 3 mole of P and 2 mol of Q would be (2005)
(a) 72 torr
(b) 140 torr
(c) 68 torr
(d) 20 torr

31. A solution has a 1 : 4 mole ratio of pentane to hexane. The vapour pressures of the pure hydrocarbons at 20°C are 440 mm Hg for pentane and 120 mm Hg for hexane. The mole fraction of pentane in the vapour phase would be (2005)
(a) 0.200
(b) 0.549
(c) 0.786
(d) 0.478

32. A solution of urea (mol. mass 56 g mol^-1) boils at 100.18°C at the atmospheric pressure. If Kf and Kb for water are 1.86 and 0.512 K kg mol^-1 respectively, the above solution will freeze at (2005)
(a) 0.654°C
(b) -0.654°C
(c) 6.54°C
(d) – 6.54°C

33. A solution containing components A and B follows Raoult’s law (2002)
(a) A – B attraction force is greater than A – A and B – B
(b) A – B attraction force is less than A – A and B-B
(c) A – B attraction force remains same as A – A and B-B
(d) volume of solution is different from sum of volume of solute and solvent.

34. A solution contains non volatile solute of molecular mass M₂. Which of the following can be used to calculate the molecular mass of solute in terms of osmotic pressure? (2002)

(m₂ = mass of solute, V = volume of solution, π = osmotic pressure)

35. 2.5 litre of 1 M NaOH solution is mixed with another 3 litre of 0.5 M NaOH solution. Then find out molarity of resultant solution. (2002)
(a) 0.80 M
(b) 1.0 M
(c) 0.73 M
(d) 0.50M

36. The beans are cooked earlier in pressure cooker because (2001)
(a) boiling point increases witlv increasing pressure
(b) boiling point decreases with increasing pressure
(c) extra pressure of pressure cooker softens the beans
(d) internal energy is not lost while cooking in pressure cooker.

37. Pure water can be obtained from sea water by (2001)
(a) centrifugation
(b) plasmolysis
(c) reverse osmosis
(d) sedimentation.

38. From the colligative properties of solution, which one is the best method for the determination of molecular weight of proteins and polymers? (2000)
(a) Osmotic pressure
(b) Lowering in vapour pressure
(c) Lowering in freezing point
(d) Elevation in boiling point

39. The vapour pressure of benzene at a certain temperature is 640 mm of Hg. A non-volatile and non-electrolyte solid, weighing 2.175 g is added to 39.08 of benzene. The vapour pressure of the solution is 600 mm of Hg. What is the molecular weight of solid substance? (1999)
(a) 69.5
(b) 59.6
(c) 49.50
(d) 79.8

40. How many g of dibasic acid (mol. weight 200) should be present in 100 mL of the aqueous solution to give strength of 0.1 N? (1999)
(a) 10 g
(b) 2 g
(c) 1 g
(d) 20 g

41. If 0.15 g of a solute, dissolved in 15 g of solvent, is boiled at a temperature higher by 0.216°C, than that of the pure solvent. The molecular weight of the substance (Molal elevation constant for the solvent is 2.16°C) is (1999)
(a) 10.1
(b) 100
(c) 1.01
(d) 1000

42. The vapour pressure of a solvent decreased by 10 mm of mercury when a non-volatile solute was added to the solvent. The mole fraction of the solute in the solution is 0.2. What should be the mole fraction of the solvent if the decrease in the vapour pressure is to be 20 mm of mercury? (1998)
(a) 0.4
(b) 0.6
(c) 0.8
(d) 0.2

43. A 5% solution of cane sugar (mol. wt. = 342) is isotonic with 1% solution of a substance X. The molecular weight of X is (1998)
(a) 68.4
(b) 171.2
(c) 34.2
(d) 136.8

44. Which of the following 0.10 m aqueous solution will have the lowest freezing point? (1997)
(a) KI
(b) C₁₂H₂₂0₁₁
(c) Al₂(S0₄)₃
(d) C₅H₁₀O₅

45. What is the molarity of H₂S0₄ solution, that has a density 1.84 g/cc at 35°C and contains 98% by weight? (1996)
(a) 18.4 M
(b) 18 M
c) 4.18 M
(d) 8.14M

46. The vapour pressure of CCL₄ at 25°C is 143 mm Hg. If 0.5 g of a non-volatile solute (mol. weight = 65) is dissolved in 100 mL CCl₄, the vapour pressure of the solution will be (1996)
(a) 199.34 mm Hg
(b) 143.99 mm Hg
(c) 141.43 mm Hg
(d) 94.39 mm Hg.

47. The relationship between osmotic pressure at 273 K when 10 g glucose (P1), 10 g urea (P2), and 10 g sucrose (P3) are dissolved in 250 mL of water is (1996)
(a) p2 > p1 > p3
(b) p2> p3> p1
(c) p1> p2> p3
(d) p3 > p1> p2

48. The concentration unit, independent of temperature, would be (1995, 1992)
(a) normality
(b) weight volume percent
(c) molality
(d) molarity.

49. According to Raoult’s law, the relative lowering of vapour pressure for a solution is equal to (1995)
(a) mole fraction of solute
(b) mole fraction of solvent
(c) moles of solute
(d) moles of solvent.

50. How many grams of CH₃OH should be added to water to prepare 150 mL solution of 2 M CH₃OH? (1994)
(a) 9.6 x 10³
(b) 2.4 x 10³
(c) 9.6
(d) 2.4

51. At 25°C, the highest osmotic pressure is exhibited by 0.1 M solution of (1994)
(a) glucose
(b) urea
(c) CaCl₂
(d) KCl

52. Which of the following salt has the same value of vant’s Hoff factor (i) as that of K₃[Fe(CN)₆]? (1994)
(a) Na₂S0₄
(b) Al(N0₃)₃
(c) Al₂(S0₄)₃
(d) NaCl

53. If 0.1 M solution of glucose and 0.1 M solution of urea are placed on two sides of the semipermeable membrane to equal heights, then it will be correct to say that (1992)
(a) there will be no net movement across the membrane
(b) glucose will flow towards glucose solution
(c) urea will flow towards glucose solution
(d) water will flow from urea solution to glucose.

54. Which one is a colligative property? (1992)
(a) Boiling point
(b) Vapour pressure
(c) Osmotic pressure
(d) Freezing point

55. Blood cells retain their normal shape in solution which are (1991)
(a) hypotonic to blood
(b) isotonic to blood
(c) hypertonic to blood
(d) equinormal to blood.

56. Which of the following aqueous solution has minimum freezing point? (1991)
(a) 0.0 l m NaCl
(b) 0.005 m C₂H₅OH
(c) 0.005 m MgI₂
(d) 0.005 m MgS0₄

57. The relative lowering of the vapour pressure is equal to the ratio between the number of (1991)
(a) solute molecules to the solvent molecules
(b) solute molecules to the total molecules in the solution
(c) solvent molecules to the total molecules in the solution
(d) solvent molecules to the total number of ions of the solute.

58. All form ideal solution except (1988)
(a) C₆H₆ and C₆H₅CH₃
(b) C₂H₆ and C₂H₅I
(c) C₆H₅CI and C₆H₅Br
(d) C₂H₅I and C₂H₅OH

59. An ideal solution is formed when its components (1988)
(a) have no volume change on mixing
(b) have no enthalpy change on mixing
(c) have both the above characteristics
(d) have high solubility.

Answer Key

Explanations

NEET AIPMT Chemistry Chapter Wise Solutions – Solid State

NEET AIPMT Chemistry Chapter Wise SolutionsPhysicsBiology

1. Which is the incorrect statement? (NEET 2017)
(a) Density decreases in case of crystals with Schottky defect.
(b) NaCl(s) is insulator, silicon is semiconductor, silver is conductor, quartz is piezoelectric crystal.
(c) Frenkel defect is favoured in those ionic compounds in which sizes of cation and anions are almost equal.
(d) FeO_0.98 has non-stoichiometric metal deficiency defect.

2. In calcium fluoride, having the fluorite structure, the coordination numbers for calcium ion (Ca²⁺) and fluoride ion (F^–) are (NEET-ll 2016)
(a) 4 and 2
(b) 6 and 6
(c) 8 and 4
(d) 4 and 8

3. Lithium has a bcc structure. Its density is 530 kg m^-3 and its atomic mass is 6.94 g mol^-1. Calculate the edge length of a unit cell of lithium metal. (N_A = 6.02 x 10²³ mol^-1) (NEET-I 2016)
(a) 527 pm
(b) 264 pm
(c) 154 pm
(d) 352 pm

4. The ionic radii of A+ and B- ions are 0.98 * 1010 m and 1.81 x 10^-10 m. The coordination number of each ion in AB is (NEET-I 2016)
(a) 8
(b) 2
(c) 6
(d) 4

5. The vacant space in bcc lattice unit cell is (2015)
(a) 48%
(b) 23%
(c) 32%
(d) 26%

6. The correct statement regarding defects in crystalline solids is (2015)
(a) Frenkel defects decrease the density of crystalline solids
(b) Frenkel defect is a dislocation defect
(c) Frenkel defect is found in halides of alkaline metals
(d) Schottky defects have no effect on the density of crystalline solids.

7. A given metal crystallises out with a cubic structure having edge length of 361 pm. If there are four metal atoms in one unit cell, what is the radius of one atom? (2015, Cancelled)
(a) 80 pm
(b) 108 pm
(c) 40 pm
(d) 127 pm

8. If a is the length of the side of a cube, the distance between the body centered atom and one comer atom in the cube will be (2014)
(a)2/√3 a
(b)4/√3 a
(c)√3/4 a
(d) √3/2 a

9. A metal has a fcc lattice. The edge length of the unit cell is 404 pm. The density of the metal is 2.72 g cm^-3. The molar mass of the metal is (NEET 2013)
(N_A Avogadro’s constant = 6.02 x 10²³ mol^-1)
(a) 27 g mol^-1
(b) 20 g mol^-1
(b) 40 g mol^-1
(d) 30 g mol^-1

10. The number of carbon atoms per unit cell of diamond unit cell is (NEET 2013)
(a) 6
(b) 1
(c) 4
(d) 8

11. A metal crystallises with a face-centred cubic lattice. The edge of the unit cell is 408 pm. The diameter of the metal atom is (2012)
(a) 288 pm
(b) 408 pm
(c) 144 pm
(d) 204 pm

12. The number of octahedral void(s) per atom present in a cubic close-packed structure is (2012)
(a) 1
(b) 3
(c) 2
(d) 4

13. Structure of a mixed oxide is cubic close packed (ccp). The cubic unit cell of mixed oxide is composed of oxide ions. One fourth of the tetrahedral voids are occupied by divalent metal A and the octahedral voids are occupied by a monovalent metal B. The formula of the oxide is (Mains 2012)
(a) ABO₂
(b) A₂B0₂
(c) A₂B₃0₄
(d) AB₂O₂

14. A solid compound XY has NaCl structure. If the radius of the cation is 100 pm, the radius of the anion (Y-) will be (Mains 2011)
(a) 275.1 pm
(b) 322.5 pm
(c) 241.5 pm
(d) 165.7 pm

15. AB crystallizes in a body centred cubic lattice with edge length ‘a’ equal to 387 pm. The distance between two oppositely charged ions in the lattice is (2010)
(a) 335 pm
(b) 250 pm
(c) 200 pm
(d) 300 pm

16. Lithium metal crystallises in a body-centred cubic crystal. If the length of the side of the unit cell of lithium is 351 pm, the atomic radius of lithium will be (2009)
(a) 151.8 pm
(b) 75.5 pm
(c) 300.5 pm
(d) 240.8 pm

17. Copper crystallises in a face-centred cubic lattice with a unit cell length of 361 pm. What is the radius of copper atom in pm? (2009)
(a) 157
(b) 181
(c) 108
(d) 128

18. Percentage of free space in a body centred cubic unit cell is (2008)
(a) 34%
(b) 28%
(c) 30%
(d) 32%

19. Which of the following statements is not correct? (2008)
(a) The number of carbon atoms in a unit cell of diamond is 4.
(b) The number of Bravais lattices in which a crystal can be categorized is 14.
(c) The fraction of the total volume occupied by the atoms in a primitive cell is 0.48.
(d) Molecular solids are generally volatile.

20. With which one of the following elements silicon should be doped so as to give p-type of semiconductor? (2008)
(a) Selenium
(b) Boron
(c) Germanium
(d) Arsenic

21. If a stands for the edge length of the cubic systems: simple cubic, body centred cubic and face centred cubic, then the ratio of radii of the spheres in these systems will be respectively (2008)
(a)1/2 a : √3/2 a : √2/2 a
(b)1 a : √3a : √2a
(c)1/2 a : √3/4 a : 1/2√2 a
(d)1/2 a : √3a : 1/√2 a

22. The fraction of total volume occupied by the atoms present in a simple cube is (2007)
(a)π/3√2
(b)π/4√2
(c)π/4
(d)π/6

23. If NaCl is doped with 10^-4 mol % of SrCl₂, the concentration of cation vacancies will be (NA = 6.02 x 10²³ mol^-1) (2007)
(a) 6.02 x 10¹⁶ mol^-1
(b) 6.02 x 10¹⁷ mol^-1
(c) 6.02 x 10¹⁴ mol^-1
(d) 6.02 x 10¹⁵ mol^-1

24. The appearance of colour in solid alkali metal halides is generally due to (2006)
(a) interstitial positions
(b) F-centres
(c) Schottky defect
(d) Frenkel defect.

25. CsBr crystallises in a body centred cubic lattice. The unit cell length is 436.6 pm. Given that the atomic mass of Cs = 133 and that of Br = 80 amu and Avogadro number being 6.02 x 10²³ mol^-1, the density of CsBr is (2006)
(a) 4.25 g/cm³
(b) 42.5 g/cm³
(c) 0.425 g/cm³
(d) 8.25 g/cm³

26. In a face-centered cubic lattice, a unit cell is shared equally by how many unit cells? (2005)
(a) 2
(b) 4
(c) 6
(d) 8

27. A compound formed by elements X and Y crystallises in a cubic structure in which the X atoms are at the comers of a cube and the Y atoms are at the face-centres. The formula of the compound is (2004)
(a) XY₃
(b) X₃Y
(c) XY
(d) XY₂

28. The pyknometric density of sodium chloride crystal is 2.165 x 10³ kg m^-3 while its X-ray density is 2.178 x 10^-3 kg m^-3. The fraction of unoccupied sites in sodium chloride crystal is (2003)
(a) 5.96
(b) 5.96 x 10^-2
(c) 5.96 x 10^-1
(d) 5.96 x 10^-3

29. When Zn converts from melted state to its solid state, it has hcp structure, then find the number of nearest atoms. (2001)
(a) 6
(b) 8
(c) 12
(d) 4

30. Cation and anion combines in a crystal to form following type of compound (2000)
(a) ionic
(b) metallic
(c) covalent
(d) dipole-dipole.

31. In cube of any crystal A-atom placed at every comers and B-atom placed at every centre of face. The formula of compound is (2000)
(a) AB
(b) AB₃
(c) A₂B₂
(d) A₂B₃

32. In crystals of which one of the following ionic compounds would you expect maximum distance between centres of cations and anions? (1998)
(a) Csl
(b) CsF
(c) LiF
(d) Lil

33. The second order Bragg diffraction of X-rays with λ = 1.00 Å from a set of parallel planes in a metal occurs at an angle 60°. The distance between the scattering planes in the crystal is (1998)
(a) 2.00 Å
(b) 1.00 Å
(c) 0.575 Å
(d) 1.15 Å

34. The edge length of face centred unit cubic cells is 508 pm. If the radius of the cation is 110 pm, the radius of the anion is (1998)
(a) 144 pm
(b) 398 pm
(c) 288 pm
(d) 618 pm

35. Schottky defect in crystals is observed when (1998)
(a) density of the crystal is increased
(b) unequal number of cations and anions are missing from the lattice
(c) an ion leaves its normal site and occupies an interstitial site
(d) equal number of cations and anions are missing from the lattice.

36. The high density of water compared to ice is due to (1997)
(a) dipole-induced dipole interactions
(b) induced dipole induced dipole interactions
(c) hydrogen bonding interactions
(d) dipole-dipole interactions.

37. For two ionic solids CaO and KI, identify the wrong statement among the following (1997)
(a) CaO has high melting point
(b) Lattice energy of CaO is much larger than that of KI
(c) KI has high melting point
(d) KI is soluble in benzene.

38. The intermetallic compound LiAg crystallizes in cubic lattice in which both lithium and silver have coordination number of eight. The crystal class is (1997)
(a) face-centred cube
(b) simple cube
(c) body-centred cube
(d) none of these.

39. The fee crystal contains how many atoms in each unit cell? (1996)
(a) 6
(b) 8
(c) 4
(d) 5

40. If we mix a pentavalent impurity in a crystal lattice of germanium, what type of semiconductor formation will occur? (1996)
(a) n-type semiconductor
(b) p-type semiconductor
(c) both (a) and (b)
(d) None of these.

41. An element (atomic mass = 100 g/mol) having bcc structure has unit cell edge 400 pm. The density of element is (1996)
(a) 7.289 g/cm³
(b) 2.144 g/cm³
(c) 10.376 g/cm³
(d) 5.188 g/cm³

42. The number of atoms in 100 g of a fcc crystal with density d = 10 g/cm³ and cell edge equal to 100 pm, is equal to (1994)
(a) 2 x 10²⁵
(b) 1 x 1o²⁵
(c) 4 x 1o²⁵
(d) 3 x 1o²⁵

43. Ionic solids, with Schottky defects, contain in their structure (1994)
(a) cation vacancies only
(b) cation vacancies and interstitial cations
(c) equal number of cation and anion vacancies
(d) anion vacancies and interstitial anions.

44. The pure crystalline substance on being heated gradually first forms a turbid liquid at constant temperature and still at higher temperature turbidity completely disappears. The behaviour is a characteristic of substance forming (1993)
(a) allotropic crystals
(b) liquid crystals
(c) isomeric crystals
(d) isomorphouS crystals.

45. On doping Ge metal with a little of In or Ga, one gets (1993)
(a) p-type semiconductor
(b) n-type semiconductor
(c) insulator
(d) rectifier.

46. In the fluorite structure, number of Ca²⁺ ion is the coordination(1993)
(a) 4
(b) 6
(c) 8
(d) 3

47. The number of atoms contained in a fcc unit cell of a monoatomic substance is (1993)
(a) 1
(b) 2
(c) 4
(d) 6

48. For orthorhombic system axial ratios are α≠β ≠ γ and the axial angles are (1991)
(a) α=β =γ ≠ 90°
(b) α = β= γ = 90°
(c) α = γ= 90°, β ≠ 90°
(d) α ≠β≠γ≠ 90°

49. Most crystals show good cleavage because their atoms, ions or molecules are (1991)
(a) weakly bonded together
(b) strongly bonded together
(c) spherically symmetrical
(d) arranged in planes.

Answer Key

Explanations

 

NEET AIPMT Chemistry Chapter Wise Solutions – p-Block Elements (Group 13 and 14)

NEET AIPMT Chemistry Chapter Wise SolutionsPhysicsBiology

1. It is because of inability of ns² electrons of the valence shell to participate in bonding that (MEET 2017)
(a) Sn²⁺ is oxidising while Pb⁴⁺ is reducing
(b) Sn²⁺ and Pb²⁺ are both oxidising and reducing
(c) Sn⁴⁺ is reducing while Pb⁴⁺‘ is oxidising
(d) Sn²⁺ is reducing while Pb⁴⁺ is oxidising.

2. Boric acid is an acid because its molecule (NEET-ll 2016)
(a) contains replaceable H⁺ ion
(b) gives up a proton
(c) accepts OH from water releasing proton
(d) combines with proton from water molecule.

3. AlF₃ is soluble in HF only in presence of KF. It is due to the formation of (NEET-ll 2016)
(a) K₃[AlF₃H₃]
(b) K₃[AlF₆]
(c) AlH₃
(d) K[AlF₃H]

4. The stability of + 1 oxidation state among Al. Ga, In and Tl increases in the sequence (2015. 2009)
(a) Al < Ga < In < Tl
(b) Tl < In < Ga < Al
(c) In < Tl < Ga < Al
(d) Ga < In < Al < Tl

5. Which of the following structure is similar to graphite?(NEET 2013)
(a) B₄C
(b) B₂H₆
(c) BN
(d) B

6. Which of these is not a monomer for a high molecular mass silicone polymer? (NEET 2013)
(a) Me₃SiCl
(b) PhSiCl₃
(c) MeSiCL₃
(d) Me₂SiCl₂

7. The basic structural unit of silicates is (NEET 2013)
(a) SiO₃^2-
(b) Si0₄^2-
(c) SiO^–
(d) SiO₄^4-

8. Which statement is wrong? (Karnataka NEET 2013)
(a) Beryl is an example of cyclic silicate.
(b) Mg₂Si0₄ is orthosilicate.
(c) Basic structural unit in silicates is the Si0₄ tetrahedron.
(d) Feldspars are not aluminosilicates.

9. Name the two type of the structure of silicate in which one oxygen atom of [Si0₄]^4- is shared? (2011)
(a) Linear chain silicate
(b) Sheet silicate
(c) Pyrosilicate
(d) Three dimensional

10. Which of the following statements is incorrect? (Mains 2011)
(a) Pure sodium metal dissolves in liquid ammonia to give blue solution.
(b) NaOH reacts with glass to give sodium silicate.
(c) Aluminium reacts with excess NaOH to give Al(OH)₃.
(d) NaHC0₃on heating gives Na₂C0₃.

11. Which of the following oxide is amphoteric? (Mains 2011)
(a) Sn0₂
(b) CaO
(c) Si0₂
(d) C0₂

12. Which one of the following molecular hydrides acts as a Lewis acid? (2010)
(a) NH₃
(b) H₂0
(c) B₂H₆
(d) CH₄

13. The tendency of BF₃, BCl₃ and BBr₃ to behave as Lewis acid decreases in the sequence (2010)
(a) BCl₃ >BF₃ > BBr₃
(b) BBr₃ > BCl₃ > BF₃
(c) BBr₃ > BF₃>BCl₃
(d) BF₃>BCl₃>BBr₃

14. The straight chain polymer is formed by (2009)
(a) hydrolysis of CH₃SiCl₃ followed by condensation polymerisation
(b) hydrolysis of (CH₃)₄Si by addition polymerisation
(c) hydrolysis of (CH₃)₂SiCl₂ followed by condensation polymerisation
(d) hydrolysis of (CH₃)₃SiCl followed by condensation polymerisation.

15. Which of the following oxidation states are the most characteristic for lead and tin respectively? (2007)
(a) +2,+4
(b) +4,+4
(c) +2,+2
(d) +4,+2.

16. Which of the following anions is present in the chain structure of silicates? (2007)
(a) (Si₂0₅^2- )n
(b) (SiO₃^2-)n
(c) SiO₄^4-
(d) Si₂O₇^6-

17. Which of the following is the most basic oxide? (2006)
(a) Se0₂
(b) Al₂0₃
(c) Sb₂0₃
(d) Bi₂0₃

18. The correct order regarding the electronegativity of hybrid orbitals of carbon is (2006)
(a) sp < sp² < sp³
(b) sp > sp² < sp³
(c) sp > sp² > sp³
(d) sp < sp² > sp³

19. Which one of the following statements about the zeolite is false? (2004)
(a) They are used as cation exchangers.
(b) They have open structure which enables them to take up small molecules.
(c) Zeolites are aluminosilicates having three dimensional network.
(d) Some of the SiO₄^4- units are replaced by AlO₄^5- and AlO₆^9- ions in zeolites.

20. Which one of the following compounds is not a protonic acid? (2003)
(a) B(OH)₃
(b) PO(OH)₃
(c) SO(OH)₂
(d) S0₂(OH)₂

21. Which compound is electron deficient? (2000)
(a) BeCl₂
(b) BCl₃
(c) CCl₄
(d) PCl₅

22. Which of the following does not show electrical conduction? (1999)
(a) Diamond
(b) Graphite
(c) Potassium
(d) Sodium

23. The type of hybridisation of boron in diborane is (1999)
(a) sp³-hybridisation
(b) sp²-hybridisation
(c) sp-hybridisation
(d) sp³d^2-hybridisation

24. Percentage of lead in lead pencil is (1999)
(a) 80
(b) 20
(c) zero
(d) 70

25. In graphite, electrons are (1997,1993)
(a) localised on each C-atom
(b) localised on every third C-atom
(c) spread out between the structure
(d) present in anti-bonding orbital.

26. Boron compounds behave as Lewis acids, because of their (1996)
(a) ionisation property
(b) electron deficient nature
(c) acidic nature
(d) covalent nature.

27. Aluminium (III) chloride forms a dimer because aluminium (1995)
(a) belongs to 3rd group
(b) can have higher coordination number
(c) cannot form a trimer
(d) has high ionization energy.

28. The BCl₃ is a planar molecule whereas NCl₃ is pyramidal because (1995)
(a) nitrogen atom is smaller than boron atom
(b) BCl₃ has no lone pair but NCl₃ has a lone pair of electrons
(c) B—Cl bond is more polar than N—Cl bond
(d) N—Cl bond is more covalent than B—Cl bond.

29. Method used for obtaining highly pure silicon, used as a semiconductor material, is (1994)
(a) crystallization
(b) zone refining
(c) oxidation
(d) electro-chemical.

30. Carbon and silicon belong to (IV) group. The maximum coordination number of carbon in commonly occurring compounds is 4, whereas that of silicon is 6. This is due to (1994)
(a) availability of low lying d-orbitals in silicon
(b) large size of silicon
(c) more electropositive nature of silicon
(d) both (b) and (c).

31. Which of the following statements about H₃B0₃ is not correct? (1994)
(a) It has a layer structure in which planar B0₃ units are joined by hydrogen bonds.
(b) It does not act as proton donor but acts as a Lewis acid by accepting hydroxyl ion.
(c) It is a strong tribasic acid.
(d) It is prepared by acidifying an aqueous solution of borax.

32. Na+, Mg2+, Al3+ and Si4+ are isoelectronic, their ionic size will follow the order (1993)
(a) Na⁺ > Mg²⁺ < Al³⁺ < Si⁴⁺
(b) Na⁺ < Mg²⁺ < Al³⁺ < Si⁴⁺
(c) Na⁺> Mg²⁺ > Al³⁺ > Si⁴⁺
(d) Na⁺ < Mg²⁺ > Al³⁺ < Si⁴⁺

33. Which of the following types of forces bind together the carbon atoms in diamond? (1992)
(a) Ionic
(b) Covalent
(c) Dipolar
(d) van der Waals

34. Water gas is produced by (1992)
(a) passing steam through a red hot coke bed
(b) saturating hydrogen with moisture
(c) mixing oxygen and hydrogen in the ratio of 1 : 2
(d) heating a mixture of C0₂ and CH₄ in petroleum refineries.

35. Which of the following is an insulator?  (1992)
(a) Graphite
(b)Aluminum
(c) Diamond
(d)Silicon

36. Glass is a (1991)
(a) liquid
(b)Solid
(c) supercooled liquid
(d) transparent organic polymer.

37. The ability of a substance to assume two or more crystalline structures is called (1990)
(a) isomerism
(b) polymorphism
(c) isomorphism
(d) amorphism.

38. The substance used as a smoke screen in warfare is (1989)
(a)SiCl₄
(b)PH₃
(c)PCl₅
(d)acetylene

Answer Key

Explanations