Which among the following are true for an irreversible isothermal expansion of an ideal gas?
$(i)$ $W = -Q$
$(ii)$ $\Delta U = 0$
$(iii)$ $\Delta H \neq 0$
$(iv)$ $\Delta T = 0$

Calculate the work done in $J$ when $63.50 \ g$ of $Zn$ is dissolved in an open beaker with hydrochloric acid at $300 \ K$. (Atomic mass of $Zn = 63.5 \ amu$)

Calculate the heat produced in $kJ$ when $280 \ g$ of $CaO$ is completely converted to $CaCO_3$ by reaction with $CO_2$ at $27 \ ^{\circ}C$ and at constant volume :-
(Given) $\Delta H^o_f (CaCO_3, s) = -1207 \ kJ/mol$
$\Delta H^o_f (CaO, s) = -635 \ kJ/mol$
$\Delta H^o_f (CO_2, g) = -394 \ kJ/mol$ (in $kJ$)

The enthalpy of combustion of methane at $25\,^{\circ}C$ is $890\,kJ$. The heat liberated when $3.2\,g$ of methane is burnt in air is.....$kJ$

For the reaction $CaCO_{3(s)} \rightleftharpoons CaO_{(s)} + CO_{2(g)}$ at $977 \ ^oC$,given $\Delta H = 176 \ kJ \ mol^{-1}$,the value of $\Delta E$ is ............. $kJ$.

At $300 \, K$ temperature,the standard heat of formation of benzoic acid $(s)$,$CO_{2(g)}$,and $H_2O_{(l)}$ are $-408$,$-393$,and $-286 \, kJ \, mol^{-1}$ respectively. At constant pressure,the heat of combustion for benzoic acid will be $..... \, kJ$.