Consider the combustion of liquid benzene at 298 ,K: Data: Molar enthalpy of…

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

Problem

Consider the combustion of liquid benzene at 298\,K:

\text{C}_6\text{H}_6(l)+\tfrac{15}{2}\text{O}_2(g)\rightarrow 6\text{CO}_2(g)+3\text{H}_2\text{O}(g)

Data:

\Delta H_f^{\circ}(\text{C}_6\text{H}_6(l)) = +49.0\,\text{kJ mol}^{-1}

\Delta H_f^{\circ}(\text{CO}_2(g)) = -393.5\,\text{kJ mol}^{-1}

\Delta H_f^{\circ}(\text{H}_2\text{O}(l)) = -285.8\,\text{kJ mol}^{-1}

Molar enthalpy of vaporization of water at 298\,K:

\Delta H_{\text{vap}}(\text{H}_2\text{O}) = +44.0\,\text{kJ mol}^{-1}

Calculate the standard enthalpy change

\Delta H^{\circ}

for the combustion reaction above. (a)

-3.27\times10^{3}\,\text{kJ}

(b)

-2.65\times10^{3}\,\text{kJ}

(c)

-3.19\times10^{3}\,\text{kJ}

(d)

-3.04\times10^{3}\,\text{kJ}