Combustion of 1 mole of benzene is expressed at C_6 H_6( l )+15/2 O_2( g ) → 6 CO_2( g )+3 H_2 O ( l ). The standard enthalpy of combustion of 2 mol…

Combustion of $\displaystyle 1$ mole of benzene is expressed at $$\mathrm{C}_6 \mathrm{H}_6(\mathrm{l})+\frac{15}{2} \mathrm{O}_2(\mathrm{~g}) \rightarrow 6 \mathrm{CO}_2(\mathrm{~g})+3 \mathrm{H}_2 \mathrm{O}(\mathrm{l}) . $$ The standard enthalpy of combustion of $\displaystyle 2$ mol of benzene is $\displaystyle -$'$\displaystyle x$' kJ. $\displaystyle x=$ $\displaystyle \_\_\_\_$. Given : 1. standard Enthalpy of formation of $\displaystyle 1$ mol of $\displaystyle \mathrm{C}_6 \mathrm{H}_6(\mathrm{l})$, for the reaction $\displaystyle 6$ C (graphite) $\displaystyle +3 \mathrm{H}_2(\mathrm{~g}) \rightarrow \mathrm{C}_6 \mathrm{H}_6(\mathrm{l})$ is $\displaystyle 48.5 \mathrm{~kJ} \mathrm{~mol}^{-1}$. 2. Standard Enthalpy of formation of $\displaystyle 1$ mol of $\displaystyle \mathrm{CO}_2(\mathrm{~g})$, for the reaction C (graphite) $\displaystyle +\mathrm{O}_2(\mathrm{~g}) \rightarrow \mathrm{CO}_2(\mathrm{~g})$ is $\displaystyle -393.5 \mathrm{~kJ} \mathrm{~mol}^{-1}$. 3. Standard and Enthalpy of formation of $\displaystyle 1$ mol of $\displaystyle \mathrm{H}_2 \mathrm{O}(\mathrm{l})$, for the reaction $$\mathrm{H}_2(\mathrm{~g})+\frac{1}{2} \mathrm{O}_2(\mathrm{~g}) \rightarrow \mathrm{H}_2 \mathrm{O}(\mathrm{l}) \text { is }-286 \mathrm{~kJ} \mathrm{~mol}^{-1} . $$