Resistance of a conductivity cell filled with 0.1 mol L–1 KCl solution is 100 Ω. If the resistance of the same cell when filled with 0.02 mol L–1 KCl solution is 520 Ω. The conductivity of 0.1 mol L–1 KCl solution is 1.29 S/m. The molar conductivity of 0.02 mol L–1 KCl solution is-
1. 134 S cm2 mol–1
2. 124 S cm2 mol–1
3. 144 S cm2 mol–1
4. 154 S cm2 mol–1
Mg(s) + 2Ag+(0.0001M) → Mg2+(0.130M) + 2Ag(s)
If EƟ(cell) for the above mentioned cell is 3.17 V, then E(cell) value will be-
(log 13=1.1)
1. 2.87 V
2. 3.08 V
3. 2.96 V
4. 2.68 V
Aluminium oxide may be electrolysed at 1000 °C to furnish aluminium metal.
The cathode reaction is Al3+ + 3e- → Al.
To prepare 5.12 kg of aluminium metal by this method would require:
(Atomic mass = 27 amu; 1 faraday=96,500 Coulombs)
1. 5.49×101 C of electricity
2. 5.49×104 C of electricity
3. 1.83×107 C of electricity
4. 5.49×107 C of electricity
Consider the following reaction:
\(\frac{4}{3} \mathrm{Al}(\mathrm{s})+\mathrm{O}_2(\mathrm{~g}) \rightarrow \frac{2}{3} \mathrm{Al}_2 \mathrm{O}_3(\mathrm{~s})\)
The minimum e.m.f. required to carry out the electrolysis of Al2O3 is:
(F = 96500 C mol–1)
1. 2.14 V
2. 4.28 V
3. 6.42 V
4. 8.56 V
The value of E0 cell for the following reaction is:
\(Cu^{2+}+ Sn^{2+}\to Cu +Sn^{4+ } \)
(Given, equilibrium constant is 106)
1. | 0.17 | 2. | 0.01 |
3. | 0.05 | 4. | 1.77 |
The potential of hydrogen electrode in contact with a solution with pH =10, is:
1. | −0.0591 V | 2. | −5.91 V |
3. | 0.0591 V | 4. | −0.591 V |
In a typical fuel cell, the reactants (R) and products (P) are:
1. | R = H2(g), O2(g); P = H2O2(l) |
2. | R = H2(g), O2(g); P = H2O(l) |
3. | R = H2(g), O2(g), C l2(g); P = HClO4(aq) |
4. | R = H2(g), N2(g); P = NH3(aq) |
1. | Cu & Zn2+ | 2. | Zn & Cu |
3. | Cu2+ & Zn2+ | 4. | Cu2+ & Zn |
1. | Increases | 2. | Decreases |
3. | Unchanged | 4. | Can't be predicted |