Q.1.
The equilibrium constant at 323°C isWhat would be its value in the presence of catalyst of a catalyst in the forward reaction?A + B ⇔ C + D + 38 kcal
-
34%
a) 1000 × conc. of catalyst
-
41%
b) 1000
-
12%
c)1000/ conc. of catalyst
-
12%
d)can't be predicted
Q.2.
Find out the solubility of Ni(OH)2 in 0.1 M NaOH. Given that the ionic product of Ni(OH)2 is 2 × 10-15.... [NEET 2020]
-
17%
a) 1 × 10-13 M
-
20%
b) 1 × 108 M
-
60%
c) 2 × 10–13 M
-
3%
d) 2 × 10–8 M
Q.3.
pH of a saturated solution of Ca(OH)2isThe solubility product (Ksp ) of Ca(OH)2 is: ... [ NEET 2019]
-
39%
a) 0.5 × 10–15
-
35%
b) 0.25 × 10–10
-
16%
c)0.125 × 10–15
-
10%
d) 0.5 × 10–10
Q.4.
Conjugate base for Bronsted acids H2O and HF are : [NEET 2019]
-
22%
a) OH- and H2F+, respectively
-
19%
b) H3O+ and F-, respectively
-
46%
c) OH- and F-, respectively
-
14%
d) H3O+ and H2F+, respectively
Q.5.
Which will make basic buffer? [NEET 2019]
-
20%
a) 50 mL of 0.1 M NaOH + 25 mL of 0.1 M CH3COOH
-
23%
b) 100 mL of 0.1 M CH3COOH + 100 mL of 0.1 M NaOH
-
43%
c) 100 mL of 0.1 M HCl + 200 mL of 0.1 M NH4OH
-
13%
d) 100 mL of 0.1 M HCl + 100 mL of 0.1 M NaOH
Explanation
Q.6.
The solubility of BaSO4 in water is 2·42 × 10–3 gL–1 at 298 K. The value of its solubility product (Ksp) will be ... [NEET 2018] (Given molar mass of BaSO4 = 233 g mol–1)
-
16%
a) 1·08 × 10-14 mol2 L–2
-
28%
b) 1·08 × 10–12 mol2 L–2
-
36%
c) 1·08 × 10–10 mol2 L–2
-
20%
d) 1·08 × 10–8 mol2 L–2
Explanation
Q.7.
For a reaction A + B ↔ 2C2 moles of A and 3 moles of B are allowed to react. If equilibrium constant is 4 at 400°C, then the mole of C at equilibrium is [ AFMC 1997]
-
4%
a) 1
-
52%
b) 2.4
-
28%
c)3.6
-
16%
d)4
Explanation
Q.8.
The dissociation constant of weak 0.1M acid solution is 4.9×10-8, its percentage ionization is .. [ AFMC 1999]
-
29%
a) 0.07%
-
43%
b) 0.007%
-
18%
c)0.7%
-
11%
d)0.0007%
Q.9.
Ionization constant of acetic acid is 1.8 ×10-The concentration of H+ ions in 0.1M solution is .. [ AFMC 2000]
-
30%
a) 1.8×10-3M
-
40%
b) 1.8×10-5M
-
15%
c) 1. 3×10-3M
-
15%
d) 1.34×10-3M
Q.10.
Solubility product of PbCl2 at 298 K is 10-At this temperature solubility of PbCl2 in mol/L is .. [ AFMC 2006]
-
12%
a)(10-6) 1/2
-
19%
b) (10-6) 1/3
-
44%
c)(0.25×10-6) 1/3
-
25%
d)(0.25×10-6) 1/2
Q.11.
If 0.1M of a weak acid is taken, and its percentage of degree of ionization is 1.34%, then its ionization constant will be..[ AFMC 2005]
-
7%
a) 0.8×10-5
-
36%
b) 1.79×10-5
-
50%
c)0.182×10-5
-
7%
d)none of the above
Q.12.
The pH of 10-8 M HCl solution is [ AFMC 2008]
-
0%
a) 8
-
35%
b) more than 8
-
41%
c)between 6 and 7
-
24%
d)slightly more than 7
Q.13.
Solubility product of a salt AB is 10-8M2 in a solution in which the concentration of A+ ions is 10-3M. The salt will precipitate when the concentration of B- ion is kept .. [ AFMC 2008]
-
0%
a) between 10-8 to 10-7 M
-
55%
b) between 10-7 to 10-8 M
-
18%
c) > 10-5 M
-
27%
d) < 10-8 M
Q.14.
An amount of solid NH4HS is placed in a flask already containing ammonia gas at a certain temperature and 0.5 atm pressure. Ammonium hydrogen sulphide decomposes to yield NH3 and H2S gases in the flask. When the decomposition reaction reaches equilibrium, the total pressure in the flask rises to 0.84 atm. The equilibrium constant for NH4HS decomposition at this temperature is [ AIEEE 2005]
-
42%
a)0.30
-
17%
b) 0.18
-
25%
c)0.17
-
17%
d)0.11
Explanation
Q.15.
Phosphorus pentachloride dissociates as follows in closed reaction vessel PCl5 → PCl3 + Cl2 If total pressure at equilibrium of the reaction mixture is P and degree of dissociation of PCl5 is 'x', the particle pressure of PCL3 will be [ AIEEE 2006]
-
18%
a)
-
45%
b)
-
0%
c)
-
36%
d)
Explanation
Q.16.
For reaction, H2 + I2 ⇔ 2HI , the equilibrium constant Kp changes with ..[ IIT 1981]
-
12%
a) Total pressure
-
6%
b) Catalyst
-
47%
c)The amount of H2 and I2 present
-
35%
d)Temperature
Q.17.
The equilibrium constant for the reaction PCl5 ⇔ PCl3 + Cl2 is 16 If the original volume of the container is reduced to half of its original volume, the value of Kp for the reaction at the same temperature will be
-
29%
a) 32
-
12%
b) 64
-
35%
c) 16
-
24%
d) 4
Q.18.
In a reaction A2 + 4B2 ⇔ 2AB4 ; ΔH
-
0%
a)Low temperature and high pressure
-
38%
b) High temperature and low pressure
-
15%
c)Low temperature and low pressure
-
46%
d)High temperature and high pressure
Q.19.
the equilibrium constant, Kc for reaction N2 + O2 ⇔ 2NO at temperature T is 4 ×10-The value of KC for reaction NO ↔ ½ N2 + ½ O2 at the same temperature is [ AIEEE 2004]
-
50%
a) 2.5 × 102
-
8%
b) 0.02
-
33%
c)4 × 10-4
-
8%
d)50
Explanation
Q.20.
In the gas phase reaction C2 H4 + H2 ⇔ C2H6, the equilibrium constant can be expresseed in units
-
36%
a) L-1 Mol-1
-
36%
b) L Mol-1
-
27%
c)L-2 Mol-2
-
0%
d)Mol L-1
Explanation
Q.21.
The first and second dissociation constant of an acid H2A are 1.0×10-5 and 5.0 ×10-10 respectively. The overall dissociation constant of the acid will be [ AIEEE 2007]
-
17%
a) 0.2 × 105
-
25%
b) 5.0 × 10-5
-
25%
c) 5.0 × 1015
-
33%
d) 5.0 × 10-15
Explanation
Q.22.
In a reversible reaction, two substances are in equilibrium. If the concentration of each one is reduced to half, the equilibrium constant will be [ Pajab CET 1997]
-
25%
a)Reduced to half of it original value
-
12%
b) Doubled
-
44%
c)Same
-
19%
d)Reduced to one forth of its original value
Q.23.
Sulphide ions in alkaline solution react with solid sulphur to form polyvalent sulphide ions. the equilibrium constant for the formation of S22- from S and S32- from S and S2- ions are 1.7 and 5.3 respectively. Equilibrium constant for the formation of S22- from S32- and S is
-
20%
a) 1.33
-
50%
b) 3.11
-
10%
c)4.21
-
20%
d)1.63
Q.24.
in a system A(l) ⇔ B(l) + 2C(l) doubling the equilibrium concentration of B will cause the equilibrium concentration of C to change to
-
8%
a) Two times its original
-
50%
b) One half of its original value
-
25%
c)(1/√2) times the original value
-
17%
d)√2 times the original value
Explanation
Q.25.
Ag+ + NH3 → [Ag(NH3)+] ; K1=6.8 × 10-3 [Ag(NH3)+] + NH3 → [Ag(NH3)2]2+ K2=1.6 × 10-3 then the formation constant of [Ag(NH3)2]2+ is [ IIT 2006]
-
10%
a) 1.08 × 10-7
-
30%
b) 1.08 × 10-5
-
60%
c) 1.08 × 10-9
-
0%
d) None of these
Q.26.
Calculate the partial pressure of carbon monoxide from the following data CO2 + C ↔ 2CO ; Kp=8 × 10-2 CaCo3 ⇔ CaO + CO2 ; Kp=2 [ Orissa JEE 2004]
-
40%
a)0.2
-
40%
b) 0.4
-
10%
c)1.6
-
10%
d)4.0
Q.27.
For the reaction, N2 + 3H2 ⇔ 2NH3 at 500°C , the value of Kp is 1.44 × 10-What will be the value of Kp at low pressure where the gases are behaving almost ideally?
-
22%
a) 1.44 × 10-5
-
22%
b) (0.082 × 773)2 × 1.44 × 10-5
-
33%
c)1.44 × 10-5 × (0.082 × 500)2
-
22%
d)1.44 × 10-5 × (0.082 × 773)3
Q.28.
The oxidation of SO2 by O2 to SO3 is an exothermic reaction. The yield of SO3 will be maximum if [ IIT 1981]
-
45%
a) Temperature is increased and pressure is kept constant
-
27%
b)Temperature is reduced and pressure is increased
-
27%
c)Both temperature and pressure are increased
-
0%
d)Both temperature and pressure are decreased
Q.29.
If equilibrium constant for a reaction is K, then standard free energy change is
-
0%
a) ΔGo=-RTlogK
-
9%
b) ΔGo=RTlnK
-
27%
c) ΔGo=RTlogK
-
64%
d) ΔGo=-2.303RTlogK
Q.30.
When two reactants A and B are mixed to give products C and D the reaction quotient, Q at the initial stage of reaction ..[ IIT 2000]
-
0%
a)Decreases with time
-
15%
b) Is independent of time
-
31%
c)Is zero
-
54%
d)Increases with time