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# The Arrhenius Equation

Common sense and chemical intuition suggest that the higher the temperature, the faster a given chemical reaction will proceed. Quantitatively this relationship between the rate a reaction proceeds and its temperature is determined by the Arrhenius Equation. At higher temperatures, the probability that two molecules will collide is higher. This higher collision rate results in a higher kinetic energy, which has an effect on the activation energy of the reaction. The activation energy is the amount of energy required to ensure that a reaction happens.

This calculator calculates the effect of temperature on reaction rates using the Arrhenius equation.

k=A*exp(-Ea/R*T)

where k is the rate coefficient, A is a constant, Ea is the activation energy, R is the universal gas constant, and T is the temperature (in kelvin).

R has the value of 8.314 x 10-3 kJ mol-1K-1

You should use this calculator to investigate the influence of temperature on the rate coefficient.

This calculator allows you to perform three different calculations:

### Sample Problem:

The reaction:

2NO2(g) -----> 2NO(g) + O2(g)

has a rate coefficient of 1.0 x 10-10 s-1 at 300 K and an activation energy of 111 kJ mol-1. What is the rate coefficient at 273 K?

(Solution: calculate the value of A for a temperature of 300 K, then use the calculated value of A to calculate k at a temperature of 273 K. We generally assume that A and the activation energy Ea do not vary with temperature).

### Input Value(s):

 rate coefficient k = sec -1 Activation Energy Ea= kJ mol-1 temperature T = K

### Result(s):

 A = sec -1

### Input Value(s):

 A = sec-1 Activation energy Ea = kJ mol-1 Temperature T = K

### Result(s):

 rate coefficient k = sec-1

### Input Value(s):

 A = sec-1 k = mol-1 Temperature T = K

### Result(s):

 Activation energy Ea = kJ mol-1

Back to the kinetics page.

Developed by Shodor
in cooperation with the Department of Chemistry,
The University of North Carolina at Chapel Hill