For the reaction the molar enthalpy change is

CHEMISTRY · Single correct · A Level · Chemistry · Energetics · Energetics

Problem

For the reaction

2\,\text{NO}_{2}(g) \rightarrow \text{N}_{2}\text{O}_{4}(g)

the molar enthalpy change is

\Delta H_{\text{rxn}}= -120\,\text{kJ}\,\text{mol}^{-1}

. If the reaction is written in the reverse direction, which of the following is the molar enthalpy change for the reverse reaction? (a)

-120\,\text{kJ}\,\text{mol}^{-1}

(b)

+120\,\text{kJ}\,\text{mol}^{-1}

(c)

-60\,\text{kJ}\,\text{mol}^{-1}

(d)

+60\,\text{kJ}\,\text{mol}^{-1}