The heat evolved in the combustion of benzene is given by the equation $C_6H_{6(l)} + 7.5 O_{2(g)} \to 3H_2O_{(l)} + 6CO_{2(g)}$,$\Delta H = -781.0 \ kcal \ mol^{-1}$. Which of the following quantities of heat energy will be evolved when $39 \ g$ of benzene is burnt in an open container?

Average $C-H$ bond energy is $416 \ kJ \ mol^{-1}$. Which of the following is correct?

The $\Delta H_f^{\circ}$ values (in $kJ \ mol^{-1}$) for graphite, diamond, and $C_{60}$ are respectively:

For the reaction,$3 C_2 H_{2(g)} \longrightarrow C_6 H_{6(g)}$,calculate the standard enthalpy change. The values of $\Delta H_f$ for $C_2 H_2$ and $C_6 H_6$ respectively are $250 \ kJ \ mol^{-1}$ and $90 \ kJ \ mol^{-1}$.

The standard enthalpy of formation,$\Delta H^o_f$ $(298 \ K)$,of methanol is represented by which of the following chemical equations?

What is the value of $\Delta H^{\circ}$ for the formation of ethanol from ethene gas and liquid water from the following data (in $kJ$)?
$(i)$ $C_2H_5OH_{(l)} + 3O_{2_{(g)}} \longrightarrow 2CO_{2_{(g)}} + 3H_2O_{(l)}$ $\Delta H^{\circ} = -1368 \ kJ$
$(ii)$ $C_2H_{4_{(g)}} + 3O_{2_{(g)}} \longrightarrow 2CO_{2_{(g)}} + 2H_2O_{(l)}$ $\Delta H^{\circ} = -1410 \ kJ$