Chapter 6, Problem 6D.7E

Interpretation Introduction

Interpretation:

The overall activation energy for the given processes responsible for its decomposition has to be estimated.

Concept Introduction:

Activation energy$(E_a)$: The energy of activation in a chemical reaction is a measure of the energy needed for the conversion of the substrate molecules to the reactive state.

The enzyme catalysts are more efficient in lower the energy activation.

Example: The decomposition of $H_2{O}_2$ require $18kcal/mol$ of energy without catalyst, but only $2kcal/mole$ in the presence of enzyme catalase.

Arrhenius equation:

• Arrhenius equation is a formula that represents the temperature dependence of reaction rates
• The Arrhenius equation has to be represented as follows

  $K=A{e}^{-E_a/RT}$

• $E_a$ represents the activation energy and it’s unit is kJ/mol
• R represents the universal gas constant and it has the value of $8.314J/K\times mol$
• T represents the absolute temperature
• A represents the frequency factor or collision frequency

The activation energy from the given information has to be calculated from the modified Arrhenius equation.

  $\text{ln}\frac{{\text{k}}_{\text{1}}}{{\text{k}}_{\text{2}}}\text{=}\frac{{\text{E}}_{\text{a}}}{\text{R}}\left[\frac{\text{1}}{{\text{T}}_{\text{2}}}\text{-}\frac{\text{1}}{{\text{T}}_{\text{1}}}\right]$