\(\,\,{\text{P}}\,\, = \,\,{\text{1}}{\text{.01}}\,\, \times \,\,{\text{1}}{{\text{0}}^{\text{5}}}\,N{m^{ - 2}},\,\,\,\Delta \,V\,\, = \,\,30600\,\, - \,\,18\,\, = \,\,30582\,\,ml\)
\(= \,\,30582\,\, \times \,\,{10^6}\,{m^3}\)
\( \Delta H\,\, = \,\,\Delta U\,\, + \,\,1.01\, \times \,\,{10^5}\,\, \times \,\,30582\,\, \times \,\,{10^{ - 6}} \)
\(40.68\,\, = \,\,\Delta U\,\, + \,\,1.01\,\, \times \,\,{10^5}\,\, \times \,\,30582\,\, \times \,\,{10^{ - 6}}\,\,\,\, \Rightarrow \,\,\,\Delta U\)
\(= \,\,37.601\,\,kJ \)