• # question_answer Out of ${{N}_{2}}$ and $N{{H}_{3}},$ which one will have greater value for van der Waals constant 'a' and which one will have greater value for van der Waals constant 'b'?

(i) As $N{{H}_{3}}$ is more easily liquefiable (due to hydrogen bonding), intermolecular forces of attraction are stronger than in ${{N}_{2}}$. Hence, $N{{H}_{3}}$ will have greater value for 'a'. (ii) As $N{{H}_{3}}$ molecule is larger in size than ${{N}_{2}}$, hence $N{{H}_{3}}$  will have greater value for 'b'. (For $N{{H}_{3}},\,\,a=4.17\,{{L}^{2}}\,$atm $mo{{l}^{-2}},$$b=0.0371\,\,L\,\,mo{{l}^{-1}}$ For ${{N}_{2}},\,\,a=1.39\,{{L}^{2}}\,$ atm $mo{{l}^{-2}},$$b=0.0319\,L\,mo{{l}^{-1}}$)