$7 \ g$ 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 $[\ln \ 5 = 1.6]$ ..... $J$

Consider the following reaction:
$C_6H_{6(l)} + \frac{15}{2} O_{2(g)} \to 6 CO_{2(g)} + 3 H_2O_{(g)}$
What are the signs of $\Delta H$,$\Delta S$,and $\Delta G$ for the above reaction?

The volume of a gas decreases from $500 \ cc$ to $300 \ cc$ when a sample of gas is compressed by an average pressure of $0.6 \ atm$. During this process $10 \ J$ of heat is liberated. The change in internal energy is......$J$

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

For the reaction at $25^{\circ} C$, $X_2O_{4(l)} \longrightarrow 2 XO_{2(g)}$, $\Delta U$ and $\Delta S$ are $2.1 \ kCal$ and $20 \ cal \ K^{-1}$ respectively. What is $\Delta G$ for the reaction at the same temperature? $(R = 2 \ cal \ K^{-1} \ mol^{-1})$

$10 \, mol$ of an ideal gas expands isothermally and reversibly from a pressure of $10 \, atm$ to $1 \, atm$ at $300 \, K$. What is the largest mass (in $kg$) which can be lifted through a height of $100 \, m$ by the energy obtained in this process (in $, kg$)?