Gibbs Free Energy Questions

For the gas phase reaction ${\text{PCl}}_5(g)\rightleftharpoons {\text{PCl}}_3(g)+{\text{Cl}}_2(g)$, which of the following conditions is correct?

Standard free energies of formation at $298\text{K}$ are $-237.2,-394.4$ and $-8.2$ for ${\text{H}}_2\text{O}(l),{\text{CO}}_2(g)$ and pentane $(g)$ respectively. The value of $E_{\text{cell}}^{\circ }$ for the pentane-oxygen fuel cell is:

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

The values of $\Delta H$ and $\Delta S$ for the reaction $\text{C}(\text{graphite})+{\text{CO}}_2(g)\to 2\text{CO}(g)$ are $170\text{kJ}$ and $170{\text{JK}}^{-1}$ respectively. This reaction will be spontaneous at:

For the reduction of silver ions with copper metal, the standard cell potential was found to be $+0.46\text{V}$ at $25^{\circ }\text{C}$. The value of standard Gibbs energy, $\Delta G^{\circ }$ will be ($F=96500{\text{C mol}}^{-1}$):

In which of the following reactions, standard reaction entropy change ($\Delta S^{\circ }$) is positive and standard Gibb’s energy change ($\Delta G^{\circ }$) decreases sharply with increasing temperature?

If the $E_{\text{cell}}^{\circ }$ for a given reaction has a negative value, which of the following gives the correct relationships for the values of $\Delta G^{\circ }$ and $K_{\text{eq}}$?