A hydrogen gas electrode is made by dipping platinum wire in a solution of HCl of pH = 10 and by passing hydrogen gas around the platinum wire at one atm pressure. The oxidation potential of the electrode would be: 

The Gibb's energy for the decomposition of $A{l}_2{O}_3$ at $500°C$ is as follows: 

2/3Al₂O₃ → 4/3Al + O₂ ; ∆_rG = + 960 k J mol^-1

The potential difference needed for the electrolytic reduction of aluminium oxide (Al₂O₃) at $500°C$ is at least,

1. 3.0 V 

2. 2.5 V 

3. 5.0 V 

4. 4.5 V 

If the  $E_{cell}^{}$ $0$for a given reaction has a negative value, then which of the following gives the correct relationship for the values of $∆G^0$ $$ $and$ $$ $$ $K_{eq}$?

1.  $∆{\mathrm{G}}^0<0;$ ${\mathrm{K}}_{\mathrm{eq}}>1$

2.  $∆{\mathrm{G}}^0<0;$ ${\mathrm{K}}_{\mathrm{eq}}<1$

3.  $∆{\mathrm{G}}^0>0;$ ${\mathrm{K}}_{\mathrm{eq}}<1$

4.  $∆{\mathrm{G}}^0>0;$ ${\mathrm{K}}_{\mathrm{eq}}>1$

Given:
(i) ${\mathrm{Cu}}^{2+}+2{\mathrm{e}}^{-}\to \mathrm{Cu}$    E^o = 0.337 V 
(ii) ${\mathrm{Cu}}^{2+}+{\mathrm{e}}^{-}\to {\mathrm{Cu}}^{+}$  E^o = 0.153 V 
Electrode potential, E^o for the reaction, 
${\mathrm{Cu}}^{+}+{\mathrm{e}}^{-}\to \mathrm{Cu}$, will be: 

1. 0.52 V

2. 0.90 V

3. 0.30 V

4. 0.38 V

For a given reaction, 
Cu(s) + 2Ag⁺ (aq) → Cu²⁺(aq)+2Ag(s); 
E⁰=0.46 V at 298 K . The equilibrium constant will be :

1. $2.4\times {10}^{10}$

2. $2.0\times {10}^{10}$

3. $4.0\times {10}^{10}$

4. $4.0\times {10}^{15}$