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
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 |
1. | Cu & Zn2+ | 2. | Zn & Cu |
3. | Cu2+ & Zn2+ | 4. | Cu2+ & Zn |
1. | Increases | 2. | Decreases |
3. | Unchanged | 4. | Can't be predicted |
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
a. | It is also known as the Leclanche cell. |
b. | The electrolyte is a moist paste of ammonium chloride (NH4Cl) and zinc chloride (ZnCl2 ). |
c. | The cathodic reaction is : MnO2 + NH4++ e-→ MnO(OH) + NH3 |
1. | Only a and b are correct | 2. | Only c is correct |
3. | Only b and c are correct | 4. | All are correct |