Which of the following changes would MOST increase the likelihood that a termolecular elementary step could become the rate-determining step of a gas-phase reaction?
a) Adding an inert gas at constant pressure to increase the total volume of the reaction vessel
b) Raising the temperature from 298K to 600K while keeping the pressure constant
c) Raising the total pressure of the reaction mixture by a factor of 1000 while keeping the temperature constant
d) Lowering the temperature from 298K to 200K to reduce molecular speeds