• # question_answer For a chemical reaction $\operatorname{A}\to Products$, the rate of disappearance of A is given by $\frac{-d{{C}_{A}}}{dt}=\frac{{{k}_{1}}{{C}_{A}}}{1+{{k}_{2}}{{C}_{A}}}$  At very low${{C}_{A}}$, the reaction of the .......... order with rate constant........ (Assume ${{k}_{1}},\,\,{{k}_{2}}$ are lesser than 1) A)  $I,\,\,{{k}_{1}}/{{k}_{2}}$     B)        $I,\,\,{{k}_{1}}$ C) $II,\,\,{{k}_{1}}/{{k}_{2}}$     D)        $II,\,\,{{k}_{1}}/({{k}_{1}}+{{k}_{2}})$

$Rate=\frac{-d{{C}_{A}}}{dt}=\frac{{{k}_{1}}{{C}_{A}}}{1+{{k}_{2}}{{C}_{A}}}$ At very low ${{C}_{A}},\,(1+{{k}_{2}}{{C}_{A}})\approx 1$ $\therefore \,\, Rate={{k}_{1}}{{C}_{A}}$ $\operatorname{Hence} order = I$ $\operatorname{Rate}\,\,constant={{k}_{1}}$