# A graph between $1/[A]^2$ vs t is plotted below where [A] is conc of [A] at time t and $[A_o]$ is initial conc and K is the rate constant of a $Rx^n$ $nA\rightarrow$ product.What is the value of rate constant

$\begin{array}{1 1}(a)\;20/3\times 10^{-6}&(b)\;10\times 10^{-6}\\(c)\;20\times 10^{-6}&(d)\;None\end{array}$

$Kt=\large\frac{1}{n-1}\big(\large\frac{1}{([A_o]+x)^{n-1}}-\frac{1}{[A_o]^{n-1}}\big)$
$[A]^{-n+1}=[A]^{-2}$
$n=3$
$(3-1)K=20\times 10^{-6}$
$K=\large\frac{20\times 10^{-6}}{2}$
$K=10\times 10^{-6}$
Hence (b) is the correct answer.
answered Dec 12, 2013