Question

The activation energy for the reaction 2H1-→ H2 + 12 is 209.5kj/m at 581k. Calculate the fraction of molecules of reactants having energy equal to a greater than activation energy.

Answer 1

Activation energy, Ea = 209.5 kJ mol−1  

Multiply by 1000 to convert in j  

Ea= 209500 J mol−1  

Temperature, T = 581 K

Gas constant, R = 8.314 JK−1 mol−1

According to Arhenious equation

K = A e –Ea/RT  

In this formula term e –Ea/RT represent the number of molecules which have energy equal or more than activation energy  

Number of molecules = e –Ea/RT  

Plug the values we get  

Number of molecules

Answer 2

Ea = 209.5 kJ mol−1

(Multiply by 1000 to convert in j )

Ea= 209500 J mol−1

Temperature, T = 581 K

Gas constant, R = 8.314 JK−1 mol−1

According to Arhenious equation

K = A e –Ea/RT

So through that we came one conclusion that no of mole =209500