Electrochemistry  MCQs

MCQs of Electrochemistry

Showing 121 to 130 out of 158 Questions
121.
At infinite dilution equivalent conductivity of NaCl, HCl and C2H5COONa each is respectively 126.45, 426.16 and 91 ohm-1 cm2. What will be its value for C2H5COOH at infinite dilution ?
(a) 201.28 ohm-1 cm2
(b) 390.71 ohm-1 cm2
(c) 698.28 ohm-1 cm2
(d) 540.48 ohm-1 cm2
Answer:

Option (b)

122.
On which factor does the ionic conductivity not depend ?
(a) Viscosity
(b) Surface tension
(c) Temperature
(d) Nature of solvent
Answer:

Option (b)

123.
Chemically rust is _____ .
(a) Fe2O3
(b) FeCO3
(c) Fe2O3 · x H2O
(d) Fe(OH)3
Answer:

Option (c)

124.
Zn is useful to prevent the corrosion of iron because _____ .
(a) E°Zn2+ | Zn > E°Fe2+ | Fe
(b) E°Zn2+ | Zn < E°Fe2+ | Fe
(c) Zn is economically cheap
(d) Zn does not melt easily
Answer:

Option (b)

125.
Ionic conductivity does not depend on which of the following factors ?
(a) Nature of the added electrolyte.
(b) Pressure.
(c) The size of ions produced and their hydration.
(d) Nature of solvent and its viscosity.
Answer:

Option (b)

126.
The solution of a hydrogen half cell has pH = 10. What will be the value of its reduction potential ?
(a) -0.0296 V
(b) -0.592 V
(c) 0.592 V
(d) 0.0592 V
Answer:

Option (b)

127.
0.25 A current is passed for 35 minutes through 400 ml 2.0 M NaCl solution. What will be pH of the solution ?
(a) 12.98
(b) 12.13
(c) 10.48
(d) 9.24
Answer:

Option (b)

128.
Decide whether the following statements are true or false :

(a) 5,79,000 coulomb electricity is required for reduction of 1 mole Cr2O72-.

(b) If 0.5 A current is passed for 2 hours, 2.246 × 1022 electrons are conducted.

(c) Aqueous solution of ZnSO4 cannot be stored in copper container. [ E°Cu2+ | Cu = +0.34 V , E°Zn2+ | Zn = -0.76 V ]

(d) Zn is better protective cover compared to tin (Sn) to prevent corrosion of iron sheets.

(a) TTFT
(b) TTFF
(c) TTTF
(d) TFFT
Answer:

Option (a)

129.
Conductivity of a solution (in Siemens unit) is directly proportional to the area of the container and concentration of the solution and inversely proportional to the length of the container. What will be the unit of proportionality constant K ?
(a) S m mol-1
(b) S m2 mol-2
(c) S m2 mol-1
(d) S2 m2 mol
Answer:

Option (c)

130.
Under which of the following conditions, reduction potential of H-electrode will be negative ?
(a) p(H2) = 1 bar, [H+] = 1.0 M
(b) p(H2) = 2 bar, [H+] = 1.0 M
(c) p(H2) = 2 bar, [H+] = 2 M
(d) p(H2) = 1 bar, [H+] = 2 M
Answer:

Option (b)

Showing 121 to 130 out of 158 Questions