- Choose the most correct option.
i. Two solutions have the ratio of their
concentrations 0.4 and ratio of their
conductivities 0.216. The ratio of
their molar conductivities will be
a. 0.54 b. 11.574
c. 0.0864 d. 1.852
ii. On diluting the solution of an
electrolyte
a. both ∧ and k increase
b. both ∧ and k decrease
c. ∧ increases and k decreasesd. ∧ decreases and k increases
iii. 1 S m^2 mol-1 is eual to
a. 10-4 S m^2 mol-1
b. 10^4 Ω-1 cm^2 mol-1
c. 10-2 S cm^2 mol-1
d. 10^2 Ω-1 cm^2 mol-1
iv. The standard potential of the cell in
which the following reaction occurs
H 2 (g,1atm) + Cu^2 ⊕(1M)
2H⊕(1M) + Cu (s), (E^0 Cu = 0.34V) is
a. -0.34 V b. 0.34 V
c. 0.17 V d. -0.17 V
v. For the cell, Pb
(s)Pb^2 ⊕(1M)Ag⊕(1M) Ag (s), if
concentraton of an ion in the anode
compartment is increased by a factor
of 10, the emf of the cell will
a. increase by 10 V
b. increase by 0.0296 V
c. decrease by 10 V
d. decrease by 0.0296 V
vi. Consider the half reactions with
standard potentials
i. Ag⊕ (aq) + e Ag (s)
E^0 = 0.8Vii. I 2 (s) + 2e 2I (aq)
E^0 = 0.53V
iii. Pb^2 ⊕ (aq) + 2e Pb (s)
E^0 = -0.13V
iv. Fe^2 ⊕ (aq) + 2e Fe (s)
E^0 = - 0.44V
The strongest oxidising and reducing
agents respectively are
a. Ag and Fe^2 ⊕^ b. Ag⊕ and Fe
c. Pb^2 ⊕ and I^ d. I 2 and Fe^2 ⊕
vii. For the reaction Ni(s) + Cu^2 ⊕ (1M)
Ni^2 ⊕ (1M) + Cu (s), E^0 cell =
0.57V ∆G^0 of the reaction is
a. 110 kJ b. -110 kJ
c. 55 kJ d. -55 kJ
viii. Which of the following is not correct?
a. Gibbs energy is an extensive
property
b. Electrode potential or cell potential
is an intensive property.
c. Electrical work = - ∆G
d. If half reaction is multiplied by a
numerical factor, the corresponding
E^0 value is also multiplied by the
same factor.
ix. The oxidation reaction that takes
place in lead storage battery during
discharge is
a. Pb^2 ⊕ (aq) + SO 42 (aq) PbSO 4 (s)
b. PbSO 4 (s) + 2H 2 O (l) PbO 2 (s)
+ 4H⊕(aq) + SO 42 (aq) + 2e
c. Pb (s) + SO 42 (aq) PbSO 4 (s) +
2e
d. PbSO 4 (s) + 2e Pb(s)
+ SO 42 (aq)Exercises