An industrial chemist studies the elementary, reversible reaction C(g) ⇌ D(g). Calorimetric measurements give ΔE=−20kJ mol−1. Kinetic studies provide Ea,fwd=110kJ mol−1 and Ea,rev=90kJ mol−1.
(a) Explain why the reaction is classified as exothermic, citing the relevant numerical evidence.
(b) At 25 °C the forward reaction is observed to be slower than the reverse reaction. Use the activation energies to rationalize this observation.
(c) A catalyst is introduced that lowers both activation energies by the same amount. Explain whether the position of equilibrium will change and how the time required to reach equilibrium will be affected.