Answer
11 kJ
Work Step by Step
$w=-\Delta nRT$ where $\Delta n$ is the number of moles of product gases-number of moles of reactant gases.
$w=-(3.70\,mol)(8.314\,Jmol^{-1}K^{-1})(78.3+273.15)K$
$=-11000\,J=-11\,kJ$
The negative sign indicates that the work is done by the system and the volume is expanding.
Therefore, expansion work done=11 kJ.
