The Arrhenius equation is
so if we plot a graph between lnK (natural log of rate constant) and 1/T (inverse of temperature in kelvin)
The straight line equation will be
lnK = lnA - Ea/RT
Where
A = constant for a particular reaction at any temperature
R = gas constant = 8.314 J /molK
So as per this equation the slope of line will be = -Ea/R
Or
Ea = -slope X R
Ea = -(-9.20X10³X 8.314) =76.49kJ /mol
Answer: activation energy = 76.49 kJ /mol