Name: Rate Law and Order of a Reaction
Uploaded: 2019-07-19
Duration: 2 min 36 s
Description: Order of reaction is nothing but the sum of the power of concentration of reactants in the rate law expression. Let's dive into this video to learn in detail.

Question

The activation energy for the uncatalysed decomposition of ammonia to its elements is

{+ 335 kJ mol}^{- 1}

. The enthalpy of reaction for this decomposition is

+ 92 kJ {mol}^{-}

. Calculate the activation energy for the uncatalysed formation of ammonia from nitrogen and hydrogen.

Accepted Answer

The decomposition of ammonia produces nitrogen and hydrogen. This process is slow in absence of catalyst but can be speed up by using suitable catalyst.

${NH}_{3} (g) ⇌ H_{2} (g) + N_{2} (g) ∆ H = 92 kJ {mol}^{- 1}; E_{a} = 335 kJ {mol}^{- 1}$

Activation energy of forward reaction $= E_{a (f)} = + 335 {kj mol}^{-}$

since $△ H = + ve$ , the reaction is endothermic.

$ΔH = + 92 kj {mol}^{- 1}$

Activation energy of backward reaction $= E_{a (b)}$

$∴ E_{a (b)} = E_{a (f)} - ΔH$

$= 335 - 92$

$= 243 kJ {mol}^{- 1}$

∴ Activation energy for the uncatalysed formation of ammonia from nitrogen and
hydrogen $= + 243 kJ {mol}^{- 1}$

The activation energy for the uncatalysed decomposition of ammonia to its elements is ${+ 335 kJ mol}^{- 1}$ . The enthalpy of reaction for this decomposition is $+ 92 kJ {mol}^{-}$ . Calculate the activation energy for the uncatalysed formation of ammonia from nitrogen and hydrogen.

Important Questions on Rates of Reaction

Learn and Prepare for any exam you want !

The activation energy for the uncatalysed decomposition of ammonia to its elements is +335 kJ mol-1. The enthalpy of reaction for this decomposition is +92 kJ mol-. Calculate the activation energy for the uncatalysed formation of ammonia from nitrogen and hydrogen.

Important Questions on Rates of Reaction

Learn and Prepare for any exam you want !

The activation energy for the uncatalysed decomposition of ammonia to its elements is ${+ 335 kJ mol}^{- 1}$ . The enthalpy of reaction for this decomposition is $+ 92 kJ {mol}^{-}$ . Calculate the activation energy for the uncatalysed formation of ammonia from nitrogen and hydrogen.