The standard reduction potentials of $2 \mathrm{H}^{+} / \mathrm{H}_2, \mathrm{Cu}^{2+} / \mathrm{Cu}, \mathrm{Zn}^{2+} / \mathrm{Zn}$ and $\mathrm{NO}_3^{-}, \mathrm{H}^{-} / \mathrm{NO}$ are 0.0 0.34 . -0.76 and 0.97 V respectively. Identify the correct statements from the following.
I. $\mathrm{H}^{+}$does not oxidise Cu to $\mathrm{Cu}^{2+}$
II. Zn reduces $\mathrm{Cu}^{2+}$ to Cu
III. $\mathrm{NO}_3^{-}$oxidises Cu to $\mathrm{Cu}^{2+}$
The standard reduction potentials of $2 \mathrm{H}^{+} / \mathrm{H}_2, \mathrm{Cu}^{2+} / \mathrm{Cu}, \mathrm{Zn}^{2+} / \mathrm{Zn}$ and $\mathrm{NO}_3^{-}, \mathrm{H}^{-} / \mathrm{NO}$ are 0.0 , +0.34 . -0.76 and 0.97 V respectively. Observe the following reactions
I. $\mathrm{Zn}+\mathrm{HCI} \rightarrow$
II. $\mathrm{Cu}+\mathrm{HCl} \rightarrow$
III. $\mathrm{Cu}+\mathrm{HNO}_3 \rightarrow$
Which reactions does not liberate $\mathrm{H}_2(g)$ ?
Aqueous $\mathrm{CuSO}_4$ solution was electrolysed by passing 2 amp of current for 10 min . What is the weight (in g) of copper deposited at cathode ?
$$ \left(\mathrm{Cu}=63 \mathrm{u} ; F=96500 \mathrm{C} \mathrm{~mol}^{-1}\right) $$