$7 \ g$ of $N_{2(g)}$ at $27 \ ^oC$ is expanded reversibly and isothermally from an initial pressure of $0.5 \ MPa$ to a final pressure of $0.1 \ MPa$. Determine the approximate work done $[\ln \ 5 = 1.6]$ ..... $J$

When $1 \ g$ of $NH_4NO_3$ is decomposed in a bomb calorimeter,the temperature of the calorimeter increases by $6.12 \ K$. If the heat capacity of the system is $1.23 \ kJ/K$,the molar enthalpy of decomposition of $NH_4NO_3$ is ........ $kJ/mol$.

The number of endothermic process/es from the following is:
$A. I_{2(g)} \rightarrow 2I_{(g)}$
$B. HCl_{(g)} \rightarrow H_{(g)} + Cl_{(g)}$
$C. H_2O_{(l)} \rightarrow H_2O_{(g)}$
$D. C_{(s)} + O_{2(g)} \rightarrow CO_{2(g)}$
$E. \text{Dissolution of ammonium chloride in water}$

The enthalpy of neutralisation of $KOH$ by a weak acid $(HA)$ is $-12.2 \ kcal \ mol^{-1}$. If the weak acid is $10 \%$ ionised,then the enthalpy of dissociation of $1 \ mole$ of $HA$ is. Given that the enthalpy of neutralisation of $KOH$ by $HCl$ is $-13.7 \ kcal \ mol^{-1}$.

For the reaction at $300 \, K$,$A_{(g)} + B_{(g)} \to C_{(g)}$,given $\Delta U = -3 \, kcal$ and $\Delta S = -10 \, cal/K$. The value of $\Delta G$ will be $...... \, cal$.

$1 \ g$ of graphite is burnt in a bomb calorimeter in excess of oxygen at $298 \ K$ and $1 \ atm$ atmospheric pressure according to the equation:
$C \ (graphite) + O_{2(g)} \rightarrow CO_{2(g)}$
During the reaction,the temperature rises from $298 \ K$ to $299 \ K$. If the heat capacity of the bomb calorimeter is $20.7 \ kJ \ K^{-1}$,what is the enthalpy change for the above reaction at $298 \ K$ and $1 \ atm$?