The enthalpy change on freezing of $1 \ mol$ of water at $5 \ ^\circ C$ to ice at $-5 \ ^\circ C$ is ..... $kJ \ mol^{-1}$.
(Given $\Delta _{fus}H = 6 \ kJ \ mol^{-1}$ at $0 \ ^\circ C$,
$C_p(H_2O, l) = 75.3 \ J \ mol^{-1} \ K^{-1}$,
$C_p(H_2O, s) = 36.8 \ J \ mol^{-1} \ K^{-1}$)

Which of the following statements is incorrect?

$A$ gas is reversibly expanded from the same initial state to the same final volume using isobaric,isothermal,and adiabatic processes. The correct order of the work done by the system on the surroundings in the three different methods is

How much $kJ$ energy is released when $6 \ mol$ of octane is burnt in air? Given $\Delta H_f^o$ for $CO_{2(g)}$,$H_2O_{(g)}$ and $C_8H_{18(l)}$ respectively are $-490$,$-240$,and $+160 \ kJ/mol$.

For the reaction $2C_6H_6(l) + 15O_2(g) \rightarrow 12CO_2(g) + 6H_2O(l)$ at $25 \ ^\circ C$,calculate the difference between the heat of reaction at constant volume and constant pressure in $kJ$.

The heat of reaction for $C_2H_2 + H_2 \rightarrow C_2H_4$ is given by the following data:
$(i) \Delta H_f^o \text{ of } H_2O_{(\ell)} = -68.3 \ K \ cal \ mol^{-1}$
$(ii) \Delta H_{comb}^o \text{ of } C_2H_2 = -337.2 \ K \ cal \ mol^{-1}$
$(iii) \Delta H_{comb}^o \text{ of } C_2H_4 = -363.7 \ K \ cal \ mol^{-1}$