Calculate the value of $$\Delta G$$ for following reaction at $$300 \mathrm{~K}$$.
$$\begin{aligned} & \mathrm{H}_2 \mathrm{O}_{(\mathrm{s})} \longrightarrow \mathrm{H}_2 \mathrm{O}_{(l)} \\ & \left(\Delta \mathrm{H}=7 \mathrm{~kJ}, \Delta \mathrm{S}=24.8 \mathrm{~J} \mathrm{~K}^{-1}\right) \end{aligned}$$
When 1 mole of gas is heated at constant volume, the temperature rises form $$273 \mathrm{~K}$$ to $$546 \mathrm{~K}$$. If heat supplied to the gas is $$\mathrm{x~J}$$, then find the correct statement from following.
What is the value of $$\mathrm{\Delta H-\Delta U}$$ for the formation of 2 moles of ammonia from $$\mathrm{H_{2(g)}}$$ and $$\mathrm{N_{2(g)}}$$ ?
Two moles of an ideal gas are expanded isothermally from $$15 \mathrm{dm}^3$$ to $$20 \mathrm{dm}^3$$. If the amount of work done is $$-6 \mathrm{dm}^{-3}$$ bar, find external pressure needed to obtain this work.