What is the enthalpy change (in J ) for converting 98 of $\mathrm{H}_2 \mathrm{O}(t)+10^{\circ} \mathrm{C}$ to $\mathrm{H}_2 \mathrm{O}(l)$ at $+20^{\circ} \mathrm{C}$ ?
$$ \left(C_p\left(\mathrm{H}_2 \mathrm{O}(\eta)\right)=75 \mathrm{Jmol}^{-1} \mathrm{~K}^{-1}\right) $$
(density of $\mathrm{H}_2 \mathrm{O}(l)=1 \mathrm{gmL}^{-1}{ }^{})$
$A, B, C$ and $D$ are some compounds. The entnalpy of formation of $A(g), B(g), C(g)$ and $D(g)$ is $9.7,-110,81$ and $-393 \mathrm{~kJ} \mathrm{~mol}^{-1}$ respectively. What is $\Delta_r H$
(in $\mathrm{kJ} \mathrm{mol}^{-1}$ ) for the given reaction ?
$$ A(g)+3 B(g) \longrightarrow C(g)+3 D(g) $$
At equilibrium of the reaction,
$$ A_2(g)+B_2(g) \rightleftharpoons 2 A B(g) $$
The concentrations of $A_2, B_2$ and $A B$ respectively are $15 \times 10^{-3} \mathrm{M}, 2.1 \times 10^{-3} \mathrm{M}$, and $1.4 \times 10^{-3} \mathrm{M}$ in a sealed vessel at 800 K . What will be $K_p$ for the decomposition of $A B$ at same temperature ?