For the equilibrium,
2H₂O $$\rightleftharpoons$$ H₃O⁺ + OH^$$-$$, the value of $$\Delta $$G^o at 298 K is approximately :

$$\underline A \,\,\buildrel {4KOH,{O_2}} \over \longrightarrow \,\,\mathop {2\underline B }\limits_{\left( {Green} \right)} \,\, + \,\,2{H_2}O$$

$$3\underline B \,\,\buildrel {4HCl} \over \longrightarrow \,\,\mathop {2\underline C }\limits_{\left( {Purple} \right)} \,\, + \,\,Mn{O_2} + 2{H_2}O$$

$$2\underline C \,\,\buildrel {{H_2}O.KI} \over \longrightarrow \,\,\mathop {2\underline A }\limits_{\left( {Purple} \right)} \,\, + \,\,2KOH\,\, + \,\,\underline D $$

In the above sequence of reactions, $${\underline A }$$ and $${\underline D }$$, respectively, are :

The coordination number of Th in K₄[Th(C₂O₄)₄(OH₂)₂] is :
(C₂O$${_4^{2 - }}$$ = Oxalato)

Given the equilibrium constant:

K_C of the reaction :

Cu(s) + 2Ag⁺ (aq) $$ \to $$ Cu²⁺ (aq) + 2Ag(s) is

10 $$ \times $$ 10¹⁵, calculate the E$$_{cell}^0$$ of this reaciton at 298 K

[2.303 $${{RT} \over F}$$ at 298 K = 0.059V]