• # question_answer In the reversible reaction, $2N{{O}_{2}}{{N}_{2}}{{O}_{4}}$ the rate of disappearance of $N{{O}_{2}}$ is equal to A) $\frac{2{{k}_{1}}}{{{k}_{2}}}\,{{[N{{O}_{2}}]}^{2}}$                    B) $2{{k}_{1}}\,{{[N{{O}_{2}}]}^{2}}-2{{k}_{2}}\,[{{N}_{2}}{{O}_{4}}]$ C) $2{{k}_{1}}{{[N{{O}_{2}}]}^{2}}-{{k}_{2}}[{{N}_{2}}{{O}_{4}}]$ D) $(2{{k}_{1}}-{{k}_{2}})\,[N{{O}_{2}}]$

 $2N{{O}_{2}}\underset{{{k}_{2}}}{\overset{{{k}_{1}}}{\mathop{\rightleftharpoons }}}\,{{N}_{2}}{{O}_{4}}$ Rate      $=\frac{1}{2}\frac{d[N{{O}_{2}}]}{2dt}$ $={{k}_{1}}{{[N{{O}_{2}}]}^{2-}}-{{k}_{2}}[{{N}_{2}}{{O}_{4}}]$ $\therefore$      Rate of disappearance of $N{{O}_{2}}=-\frac{d[N{{O}_{2}}]}{dt}$ $=2{{k}_{1}}{{[N{{O}_{2}}]}^{2}}-2{{k}_{2}}[{{N}_{2}}{{O}_{4}}]$