Question

Consider the inter conversion of nitrosotriaceto amine into nitrogen, phorone and water.



The reaction is $1^{st}$ order in each direction, with an equilibrium constant of ${10}^4$. The activation energy for the backward reaction is 57.45 kJ/mol. Assume its Arrhenius pre exponential factor as ${10}^{12}{s}^{-1}$.

What is the expected forward constant at 300 K, if we initiate this reaction starting with only reactant?

• A. ${10}^2$
• B. ${10}^6$
• C. ${10}^8$
• D. ${10}^4$

Answer 1

The correct option is B ${10}^6$

$log{k}_b=logA-\frac{E_b}{2.303RT}$
$log{k}_b=12-\frac{57450}{2.303\times 8.314\times 300}$
$log{k}_b=12-10=2$
$\Rightarrow k_b={10}^2$
$K_c=\frac{k_f}{k_b}$
${10}^4=\frac{k_f}{{10}^2}\Rightarrow k_f={10}^6$