The number of Faradays (F) required to produce 20 g of calcium from molten CaCl₂ (Atomic mass of Ca = 40 g mol^–1) is:

1. 2

2. 3

3. 4

4. 1

Molten sodium chloride conducts electricity due to the presence of: 

1. Free ions.

2. Free molecules.

3. Free electrons.

4. Atoms of sodium and chlorine.

The electrode potential of Cu electrode dipped in 0.025 M CuSO₄ solution at 298 K is:

(standard reduction potential of Cu = 0.34 V)

1. 0.047 V

2. 0.293 V

3. 0.35 V

4. 0.387 V

During the electrolysis of a highly concentrated H₂SO₄ solution, which is released at the anode?

1. H₂

2. O₂

3. S₂O₈^2–

4. Both (1) & (3)

The electrode potential for Mg electrode varies according to the equation

\(E_{Mg^{2+}/Mg}\ = \ E_{Mg^{2+}/Mg}^{o} \ - \ \frac{0.059}{2}log\frac{1}{[Mg^{2+}]}\) 

The graph of E_{Mg²⁺ / Mg} vs log [Mg²⁺] among the following is:

1.		2.
3.		4.

$\begin{array}{l}{E}_{{\mathrm{Cr}}_2{\mathrm{O}}_7^{2-}/{\mathrm{Cr}}^{3+}}^{⊝}=1.33\mathrm{V}; E_{{\mathrm{Cl}}_2/{\mathrm{Cl}}^{-}}^{\ominus }=1.36\mathrm{V}\\ E_{\mathrm{Mn}{\mathrm{O}}_4^{-}/{\mathrm{Mn}}^{2+}}^{⊝}=1.51\mathrm{V}; E_{{\mathrm{Cr}}^{3+}/\mathrm{Cr}}^{\ominus }=-0.74\mathrm{V}\end{array}$

Use the data given above to find out the most stable ion in its reduced form.

The cell constant of a conductivity cell-

The half-cell reaction at the anode during the electrolysis of aqueous sodium chloride solution  is represented by : 

1. Na⁺(aq) + e^- ⟶ Na(s) ; \(E_{cell}^{o} \ = \ -2.71 \ V \)

2. 2H₂O(l) ⟶ O₂(g) + 4H⁺(aq) + 4e^- ; \(E_{cell}^{o} \) = 1.23 V

3. H⁺(aq) + e^- ⟶ \(\frac{1}{2}\)H₂(g) ; \(E_{cell}^{o} \) = 0.00 V

4. Cl^-(aq) ⟶ \(\frac{1}{2}\)Cl₂(g) + e- ; \(E_{cell}^{o}\) $= 1.\mathrm{36 }\mathrm{V}$

The unit of specific conductance is:

For the cell, Ti/Ti⁺(0.001M)||Cu²⁺(0.1M)|Cu, ${\mathrm{E}}_{\mathrm{cell}}^{\mathrm{o}}$ $$at

25 $°$C is 0.83 V. E_cell can be increased :

1. By increasing [Cu²⁺]

2. By increasing [Ti⁺]

3. By decreasing [Cu²⁺]

4. None of the above.