If 5 moles of an ideal gas expands from $$10 \mathrm{~L}$$ to a volume of $$100 \mathrm{~L}$$ at $$300 \mathrm{~K}$$ under isothermal and reversible condition then work, $$\mathrm{w}$$, is $$-x \mathrm{~J}$$. The value of $$x$$ is __________.

(Given R = 8.314 J K$$^{-1}$$ mol$$^{-1}$$)

Consider the following reaction at $$298 \mathrm{~K} \cdot \frac{3}{2} \mathrm{O}_{2(g)} \rightleftharpoons \mathrm{O}_{3(g)} \cdot \mathrm{K}_{\mathrm{P}}=2.47 \times 10^{-29}$$. $$\Delta_r G^{\ominus}$$ for the reaction is _________ $$\mathrm{kJ}$$. (Given $$\mathrm{R}=8.314 \mathrm{~JK}^{-1} \mathrm{~mol}^{-1}$$)

Two reactions are given below:

$$\begin{aligned} & 2 \mathrm{Fe}_{(\mathrm{s})}+\frac{3}{2} \mathrm{O}_{2(\mathrm{~g})} \rightarrow \mathrm{Fe}_2 \mathrm{O}_{3(\mathrm{~s})}, \Delta \mathrm{H}^{\circ}=-822 \mathrm{~kJ} / \mathrm{mol} \\ & \mathrm{C}_{(\mathrm{s})}+\frac{1}{2} \mathrm{O}_{2(\mathrm{~g})} \rightarrow \mathrm{CO}_{(\mathrm{g})}, \Delta \mathrm{H}^{\circ}=-110 \mathrm{~kJ} / \mathrm{mol} \end{aligned}$$

Then enthalpy change for following reaction $$3 \mathrm{C}_{(\mathrm{s})}+\mathrm{Fe}_2 \mathrm{O}_{3(\mathrm{~s})} \rightarrow 2 \mathrm{Fe}_{(\mathrm{s})}+3 \mathrm{CO}_{(\mathrm{g})}$$ is _______ $$\mathrm{kJ} / \mathrm{mol}$$.

An ideal gas undergoes a cyclic transformation starting from the point A and coming back to the same point by tracing the path $$\mathrm{A} \rightarrow \mathrm{B} \rightarrow \mathrm{C} \rightarrow \mathrm{A}$$ as shown in the diagram above. The total work done in the process is __________ J.