One mole of an ideal gas is allowed to expand reversibly and adiabatically from a temperature of $27\,^oC$. If the work done during the process is $3\,kJ$,the final temperature will be equal to $(C_v = 20\,J\,K^{-1} \, mol^{-1})$

Identify the correct statements from the following:
$I$. $\Delta_{r} G$ is zero for $A \rightleftharpoons B$ reaction.
$II$. The entropy of pure crystalline solids approaches zero as the temperature approaches absolute zero.
$III$. $\Delta U$ of a reaction can be determined using a bomb calorimeter.

For a diatomic ideal gas in a closed system,which of the following plots does not correctly describe the relation between various thermodynamic quantities?

Identify the correct statement$(s)$:

An ideal gas is expanded from $(p_1, V_1, T_1)$ to $(p_2, V_2, T_2)$ under different conditions. The correct statement$(s)$ among the following is(are):
[$A$] The work done on the gas is maximum when it is compressed irreversibly from $(p_2, V_2)$ to $(p_1, V_1)$ against constant pressure $p_1$.
[$B$] The work done by the gas is less when it is expanded reversibly from $V_1$ to $V_2$ under adiabatic conditions as compared to that when expanded reversibly from $V_1$ to $V_2$ under isothermal conditions.
[$C$] The change in internal energy of the gas is $(i)$ zero,if it is expanded reversibly with $T_1=T_2$,and $(ii)$ positive,if it is expanded reversibly under adiabatic conditions with $T_1 \neq T_2$.
[$D$] If the expansion is carried out freely,it is simultaneously both isothermal as well as adiabatic.

The value of $\Delta H$ for cooling $2 \ mol$ of an ideal monoatomic gas from $225^{\circ} C$ to $125^{\circ} C$ at constant pressure will be [given $C_{p} = \frac{5}{2} R$]. (in $R$)