Answer
-41.2 kJ
Work Step by Step
$\Delta H^{o}_{rxn}=\Sigma n_{p}\Delta H_{f}^{o}(products)-\Sigma n_{r}\Delta H_{f}^{o}(reactants)$
$=[1(\Delta H^{o}_{f,\,H_{2}(g)})+1(\Delta H^{o}_{f,\,CO_{2}(g)})]-[1(\Delta H^{o}_{f,\,CO(g)})+1(\Delta H^{o}_{f,\,H_{2}O(g)})]$
$=[1(0)+1(-393.5\,kJ)]-[1(-110.5\,kJ)+1(-241.8\,kJ)]$
$=-41.2\,kJ$