$\Delta H_f^o$ of water is $-285.5\, kJ\, mol^{-1}$. If enthalpy of neutralisation of monoacidic strong base is $-57.3\, kJ\, mol^{-1}$,$\Delta H_f^o$ of $OH^{-}$ ion will be $.....\, kJ\, mol^{-1}$.

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 $kJ$)

Chloroform has $\Delta H_{vaporization} = 29.2 \ kJ/mol$ and boils at $61.2 \ ^oC$. What is the value of $\Delta S_{vaporization}$ for chloroform? $...... \ J/mol \ K$

$A$ steel steam boiler has a mass of $900 \, kg$ and contains $400 \, kg$ of water. If the boiler and water receive only $70 \%$ of the heat supplied,how much heat in $kcal$ is required to raise the temperature of the boiler and water from $10 \, ^oC$ to $100 \, ^oC$? (Specific heat of steel = $0.11 \, kcal/kg \cdot K$,Specific heat of water = $1.0 \, kcal/kg \cdot K$)

For a dimerization reaction,$2 A_{(g)} \rightarrow A_{2(g)}$ at $298 \ K$,$\Delta U^{\ominus} = -20 \ kJ \ mol^{-1}$,$\Delta S^{\ominus} = -30 \ J \ K^{-1} \ mol^{-1}$,then the $\Delta G^{\ominus}$ will be........ $J$

For an ideal gas, consider only $P-V$ work in going from an initial state $X$ to the final state $Z$. The final state $Z$ can be reached by either of the two paths shown in the figure. Which of the following choice(s) is (are) correct? [take $\Delta S$ as change in entropy and $w$ as work done].
(A) $\Delta S_{X \to Z} = \Delta S_{X \to Y} + \Delta S_{Y \to Z}$
(B) $w_{X \to Z} = w_{X \to Y} + w_{Y \to Z}$
(C) $w_{X \to Y \to Z} = w_{X \to Y} + w_{Y \to Z}$
(D) $\Delta S_{X \to Y \to Z} = \Delta S_{X \to Y}$