Question

The hydrolysis of ethyl acetate in alkaline conditions yields acetate ion and ethanol. The rate

of the reaction increases 6.37 times its original value when the temperature is increased from

15°C to 45°C. Calculate the activation energy of this reaction.

Answer 1

K₁= 1

K₂= 6.37

T₁= 15°C = 288K

T₂= 45°C = 318K

E_a=?

R= 8.314J/K.mol

Using the derived form of Arrhenius equation

lnK₁/K₂ = E_a/R x (1/T₂ - 1/T₁)

ln1/6.37 = E_a/8.314 x (1/318 - 1/288)

-1.85= E_a/8.314 x (-3.76 x 10^-4)

E_a= -1.85x8.314/-3.76x10^-4

E_a= 40907J = 41KJ