Question

In: Chemistry

If a 1st order reaction has a rate constant of 2.30 s^-1 at 25 degree C,...

If a 1st order reaction has a rate constant of 2.30 s^-1 at 25 degree C, and at a frequency factor of 2.51*10^5, calculate the activation energy.

A) 9715 J/mol

B)186 J/mol

C) -186 J/mol

D) 2.51*10^4 J/mol

E) 2.51*10^-4 J/mol

Expert Solution

Activation energy is the additional amount of energy is supplied to the reactant molecule to reach the threshold state of energy.

Activation energy is related to Arrhenius equation.

K= rate constant

A= frequency factor

Ea= activation energy

R= gas constant=8.314 J/K mol

T= temperature

Now apply the law

and here T=25⁰C = 298K

we get

Answer.

queen_honey_blossom answered 2 years ago

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