Enthalpy of formation of $\mathrm{CO}_2(\mathrm{~g}), \mathrm{H}_2 \mathrm{O}(\mathrm{l})$ and $\mathrm{C}_6 \mathrm{H}_{12} \mathrm{O}_6(\mathrm{~s})$ are $-393,-286$ and $-1170 \mathrm{~kJ} \mathrm{~mol}^{-1}$ respectively. The quantity of heat liberated when 18 g of $\mathrm{C}_6 \mathrm{H}_{12} \mathrm{O}_6(s)$ is burnt completely in oxygen is

For which reaction $\Delta H \neq \Delta U ?$

At $298 \mathrm{~K}, \Delta_r U^{\ominus}$ and $\Delta_r S^{\ominus}$ for the following reaction are -10.5 kJ and $+44.1 \mathrm{JK}^{-1} ; 2 X(\mathrm{~g})+Y(\mathrm{~g}) \longrightarrow 2 Z(\mathrm{~g})$ What is $\Delta_r G^{\ominus}$ (in kJ ) for this reaction? $\left(R=8.314 \mathrm{JK}^{-1} \mathrm{~mol}^{-1}\right)$

Consider the following reaction

$$ A(g)+3 B(g) \longrightarrow 2 C(g) ; \Delta H^{\ominus}=-24 \mathrm{~kJ} $$

At $25^{\circ} \mathrm{C}$, if $\Delta G^{\ominus}$ of the reaction is -9 kJ , the standard entropy change (in $\mathrm{JK}^{-1}$ ) of the same reaction at same temperature is