Calculate the molar mass of nonelectrolyte solute when 6 gram of it is dissolved in 1 $\text{dm}^3$ water has osmotic pressure $2.4\ \text{atm}$ at 300 K $(R = 0.0821\ \text{atm dm}^3\ \text{K}^{-1}\ \text{mol}^{-1})$

A galvanic cell consist copper electrode and standard hydrogen electrode. If $E^\circ\left(\text{Cu}^{+2}_{(aq)} | \text{Cu}_{(s)}\right) = +0.34\,\text{V}$, then identify a reaction taking place at positive electrode during working of cell.

If standard reduction potential of Zn, Ni and Fe are $-0.76\,\text{V}$, $-0.23\,\text{V}$ and $-0.44\,\text{V}$ respectively. For the reaction (Stated below) to be spontaneous find out electrodes X and Y considering above electrode potentials
$\text{X}_{(s)} + \text{Y}^{+2}_{(aq)} \longrightarrow \text{X}^{+2}_{(aq)} + \text{Y}_{(s)}$

If standard reduction potential of four electrodes A, B, C, D are $+2.5\,\text{V}, +3.0\,\text{V}, -2.0\,\text{V}$ and $-1.5\,\text{V}$ respectively. When is the standard emf of cell maximum?