Question

The rate constant of a reaction at 500k and 700k are 0.02 s-1 and 0.07 s-1 respectively the value of activation energy is (in KJ)​

Answer 1

solution:available both as a colorless crystalline solid and processed into prills for specific applications. Soluble in water. Does not readily burn but will do so if contaminated with combustible material. Accelerates the burning of combustible material. Produces toxic oxides of nitrogen during combustion. Used to make fertilizers and explosives, and as a nutrient in producing antibiotics and yeast.

CAMEO Chemicals

Answer 2

Concept :- Rate constant (k) is relates to activation energy Ea by the equation :-

$k = A {e}^{ \frac{ - Ea}{RT} }$

where,

A = Arrhenius constant.

SOLUTIONS :-

At 500 K , K = 0.02

$0.02 = A {e}^{ - \frac{Ea}{500R} } .....(1)\\ at \: 700k \\ 0.07 = A {e}^{ - \frac{Ea}{700R} }......(2) \\ divinding \: equation(2) \: by \: (1) \\ \frac{0.07}{0.02} \: = \frac{ \:A {e}^{ - \frac{Ea}{700r} }}{ \:A{e}^{ - \frac{Ea}{500R} }} \\ \\ = > \frac{7}{2} = {e}^{ \frac{Ea}{500R} - \frac{Ea}{700R} } \\ \\ = > \frac{7}{2} = {e}^{ \frac{ 200Ea}{3500R} } \\ \\ = > ln( \frac{7}{2} ) = \frac{ 200Ea}{3500R} \\ \\ = > ln( \frac{7}{2} ) = \frac{2Ea}{35R} \\ \\ = > Ea = \frac{35R}{2} ln( \frac{7}{2} ) \\ \\ = > Ea = 182.27 \\ \\ = > Ea = 0.18227 \: kj$