For the reaction $2X_{(g)} + Y_{(g)} \to 2Z_{(g)}$ at $298 \ K$,$\Delta U = -10.5 \ kJ$ and $\Delta S^o = -10.5 \ J/K$. Calculate $\Delta G^o$ for the reaction. Will the reaction be spontaneous or not? Explain.

Arrange the following isothermal processes in order of the magnitude of the work $(w)$ involved between states $1$ and $2$.
$A$. Expansion in single stage $(w_A)$
$B$. Expansion in multi stages $(w_B)$
$C$. Compression in single stage $(w_C)$
$D$. Compression in multi stages $(w_D)$

The enthalpies of combustion of $S_{(s)}$ and $H_{2(g)}$ are $-300 \ kcal \ mol^{-1}$ and $-290 \ kcal \ mol^{-1}$ respectively. Given the following reactions:
$SO_{3(g)} + H_2O_{(l)} \rightarrow H_2SO_{4(l)}$; $\Delta H = -130 \ kcal \ mol^{-1}$
$SO_{2(g)} + 1/2 O_{2(g)} \rightarrow SO_{3(g)}$; $\Delta H = -100 \ kcal \ mol^{-1}$
$S_{(s)} + O_{2(g)} \rightarrow SO_{2(g)}$; $\Delta H = -300 \ kcal \ mol^{-1}$
$H_{2(g)} + 1/2 O_{2(g)} \rightarrow H_2O_{(l)}$; $\Delta H = -290 \ kcal \ mol^{-1}$
The enthalpy of formation of $H_2SO_{4(l)}$ is:

Two moles of an ideal monoatomic gas are allowed to expand adiabatically and reversibly from $300 \ K$ to $200 \ K$. The work done in the process will be $..... \ kJ$.

The heat of neutralization of a strong acid and a strong alkali is $-57.0 \ kJ \ mol^{-1}$. The heat released when $0.5 \ mole$ of $HNO_3$ solution is mixed with $0.2 \ mole$ of $KOH$ is ....$kJ$

Enthalpy of neutralisation of acetic acid by $NaOH$ is $-50.6 \ kJ/mol$ and the heat of neutralisation of a strong acid with a strong base is $-55.9 \ kJ/mol$. What is the value of $\Delta H$ for the ionisation of $CH_3COOH$ in $kJ/mol$?