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Arrhenius Equation Calculator
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The Arrhenius equation is used to calculate the value of âkâ at various temperatures and also the activation energy of a reaction.
In any chemical reaction,the rate of reaction depends on the number of collisions between the reactant atoms and molecules, on the fraction of the collisions that occur with proper orientation, and on the fraction that overcomes Ea (activation energy). The rate constant is given by
k = A $e^{\frac{âE_{a}}{RT}}$
where:
A is the frequency factor,
Ea is the activation energy,
R = gas constant = 8.314 J/mol K,
$e^{\frac{âE_{a}}{RT}}$ is the fraction of molecules with minimum energy for reaction at temperature T.

Arrhenius equation calculator helps to calculate the rate constant if above all quantities are given.

Steps for Arrhenius Equation Calculator

Step 1 :

Analyze the given quantities in the problem

Step 2 :

Use the formula

k = A $e^{\frac{–E_{a}}{RT}}$

where:
A is the frequency factor,
Eis the activation energy,
R = gas constant = 8.314 J/mol K,
T = temperature

Substituting the given values, you will get the rate constant.

Problems on Arrhenius Equation Calculator

1. Calculate the rate constant of a chemical reaction if frequency factor is 0.2 Hz, activation energy 10 KJ mol-1 and temperature 293 K?

Step 1 :

Given: Frequency factor f = 0.2 Hz = 0.2 s-1,

Activation energy Ea = 10 KJ mol-1,

Temperature T = 293 K

Step 2 :

The rate constant is given by

k = A $e^{\frac{–E_{a}}{RT}}$

= 0.2 $e^{\frac{- 10 }{8.314 \times 293}}$

Rate constant k = 2.437 $\times$ 10-10  s-1

2. The chemical reaction takes place, its frequency factor is 0.5 s-1, actvation energy is 40 KJ/mol having temperature 300K. Calculate its rate constant?

Step 1 :

Given: Frequency factor f = 0.5 Hz = 0.5 s-1,

Activation energy E= 40 KJ mol-1,

Temperature T = 300 K

Step 2 :

The rate constant is given by

k = A $e^{\frac{–E_{a}}{RT}}$

= 0.5 $e^{\frac{- 40 }{8.314 \times 300}}$

Rate constant k = 5.42 $\times$ 10-8 s-1