Two elementary gas-phase reactions have identical pre-exponential factors

CHEMISTRY · Subjective · AP · Chemistry · Kinetics · Kinetics

Problem

Two elementary gas-phase reactions have identical pre-exponential factors. At 298 K, Reaction X has

E_a = 55\,{\rm kJ\,mol^{-1}}

and Reaction Y has

E_a = 75\,{\rm kJ\,mol^{-1}}

. Calculate the ratio

k_X/k_Y

of their rate constants at 298 K. Use

R = 8.314\,{\rm J\,mol^{-1}\,K^{-1}}

and report your answer to two significant figures.