Question

For the complex $A{g}^{+}+2N{H}_3\rightleftharpoons \left[Ag\right(N{H}_3{)}_2^{+}]$
$\left(\frac{dx}{dt}\right)=2\times {10}^7{L}^{2}mo{l}^{-2}{s}^{-1}\left[A{g}^{+}\right][N{H}_3{]}^2-1\times {10}^{-2}{s}^{-1}[Ag\left(N{H}_3{)}_2^{+}\right]$
Hence ratio of rate constants of the forward and backward reaction is:

• A. $2\times {10}^7{L}^{2}mo{l}^{-2}$
• B. $2\times {10}^9{L}^{2}mo{l}^{-2}$
• C. $1\times {10}^2{L}^{2}mo{l}^{-2}$
• D. $0.5\times {10}^9{L}^{2}mo{l}^{-2}$

Answer 1

The correct option is B $2\times {10}^9{L}^{2}mo{l}^{-2}$

For ratio of rate constant suppose $\left(\frac{dx}{dt}\right)$ = 0
$⟹2\times {10}^7\left[A{g}^{+}\right][N{H}_3{]}^2-1\times {10}^{-2}[Ag\left(N{H}_3{)}_2^{+}\right]=0$
$⟹\frac{k_f}{k_b}=\frac{2\times {10}^7}{1\times {10}^{-2}}=2\times {10}^9{L}^{2}mo{l}^{-2}$