Question

The activation energy for the reaction NO2 (g )+ CO (g) ⟶ NO (g) + CO2 (g) is Ea = 218 kJ/mol and the change in enthalpy for the reaction is ΔH = -252 kJ/mol . What is the activation energy for the reverse reaction? Enter your answer numerically and in terms of kJ/mol.

Answer 1

Answer:

$470\frac{KJ}{mol}$

Explanation:

The activation energy represents the energy barrier that reagents must pass to transform into products (or products to transform into reagents in a reverse reaction)

For any reaction, the change in enthalpy is related to the activation energy by the equation

$\Delta H =E_{a\ direct}-E_{a\ reverse}$

So, the activation energy for the reverse reaction is

$E_{a\ reverse}=E_{a\ direct}-\Delta H =218 \frac{KJ}{mol} - (-252)\frac{KJ}{mol}=470\frac{KJ}{mol}$