The equilibrium constant of the reaction

$$A(s)+2 B^{+}(a q) \rightleftharpoons A^{2+}(a q)+2 B(s)$$

$$E_{\text {cell }}^{\circ}=0.0295 \mathrm{~V} \text { is } \quad\left[\frac{2.303 R T}{F}=0.059\right]$$

Using the standard electrode potential, find out the pair between which redox reaction is not feasible.

E$$^\Theta $$ values Fe³⁺ / Fe²⁺ = + 0.77; I₂ / I^$$-$$ = + 0.54 Cu²⁺ / Cu = + 0.34; Ag⁺ / Ag = 0.80 V

The molar conductivities of KCl, NaCl and KNO₃ are 152, 128 and 111 S cm² mol^$$-$$1 respectively. What is the molar conductivity of NaNO₃?

The approximate time duration in hours to electroplate 30 g of calcium from molten calcium chloride using a current of 5 A is (Atomic mass of Ca = 40)