When of ethanol,

CHEMISTRY · Subjective · A Level · Chemistry · Energetics · Energetics

Problem

When

5.00\,\text{g}

of ethanol,

\mathrm{C_2H_5OH(l)}

, burns completely in

\mathrm{O_2(g)}

298\,\text{K}

and

1\,\text{bar}

148\,\text{kJ}

of heat is released. All products are formed under standard conditions as

\mathrm{CO_2(g)}

and

\mathrm{H_2O(l)}

. Given

\Delta H_f^\circ(\mathrm{CO_2(g)}) = -393.5\,\text{kJ mol}^{-1}

\Delta H_f^\circ(\mathrm{H_2O(l)}) = -285.8\,\text{kJ mol}^{-1}

, and the molar mass of ethanol is

46.07\,\text{g mol}^{-1}

, calculate the standard enthalpy of formation,

\Delta H_f^\circ

, of

\mathrm{C_2H_5OH(l)}

\text{kJ mol}^{-1}