$1 \, \text{mole}$ of $H_2SO_4$ is mixed with $2 \, \text{moles}$ of $NaOH$. The heat evolved will be

For the gas phase reaction,$PCl_{5(g)} \rightleftharpoons PCl_{3(g)} + Cl_{2(g)}$,which of the following conditions are correct?

When $1 \ g$ equivalent of a strong acid reacts with a strong base,the heat released is $13.5 \ kcal$. When $1 \ g$ equivalent of $H_2A$ is completely neutralized against a strong base,$13 \ kcal$ is released. When $1 \ g$ equivalent of $B(OH)_2$ is completely neutralized against a strong acid,$10 \ kcal$ of heat is released. Calculate the enthalpy change when $1 \ mole$ of $H_2A$ is completely neutralized by $B(OH)_2$ in $kcal$.

The standard entropies of $X_2, Y_2$ and $XY_3$ are $60, 40$ and $50 \ J \ K^{-1} \ mol^{-1}$ respectively. For the reaction $X_2 + 3Y_2 \rightleftharpoons 2XY_3; \Delta H = -60 \ kJ$ to be at equilibrium,the temperature should be.....$K$

Fill in the blanks given below:
$(i)$ The law of thermodynamics is actually the law of ......... .
$(ii)$ $A$ thermometer measures temperature according to the ......... law of thermodynamics.
$(iii)$ The foundation of thermochemistry is based on the ......... law of thermodynamics.
$(iv)$ The amount of heat required to raise the temperature of a substance by $1^{\circ}C$ is called the ......... of that substance.

The enthalpies of formation of gaseous $N_2O$ and $NO$ at $298 \ K$ are $82.0$ and $90.0 \ kJ \ mol^{-1}$ respectively. The enthalpy change of the reaction $N_2O_{(g)} + \frac{1}{2} O_{2(g)} \rightarrow 2 NO_{(g)}$ is