For the reactions,$C + O_2 \to CO_2; \Delta H = -393 \ J$
$2Zn + O_2 \to 2ZnO; \Delta H = -412 \ J$

One mole of an ideal gas is allowed to expand reversibly and adiabatically from a temperature of $27\,^oC$. If the work done during the process is $3\,kJ$,the final temperature will be equal to $(C_v = 20\,J\,K^{-1} \, mol^{-1})$

Standard enthalpy of vapourisation for $CCl_4$ is $30.5 \ kJ \ mol^{-1}$. Heat required for vapourisation of $284 \ g$ of $CCl_4$ at constant temperature is . . . . . . $kJ$. (Given molar mass in $g \ mol^{-1} ; C=12, Cl=35.5$ )

The difference between enthalpy change and internal energy change for the combustion of one mole of ethyl alcohol is

Calculate the difference between $\Delta H$ and $\Delta U$ for the following reaction at $25^{\circ} C$:
$C_2H_{6(g)} + 3.5O_{2(g)} \rightarrow 2CO_{2(g)} + 3H_2O_{(l)}$
(Given: $R = 8.314 \ J \ K^{-1} \ mol^{-1}$) (in $kJ$)

Molar enthalpy change for vapourisation of $1.0 \ mol$ of water at $1.0 \ bar$ and $100 ^{\circ} C$ is $41.0 \ kJ \ mol^{-1}$. If water vapour is assumed to be an ideal gas,the internal energy change for $1.0 \ g$ of water in $kJ$ is