Consider the elementary step
A+B+M⟶AB+M
where M is a solvent molecule present in large excess and appears unchanged on both sides of the equation. Which statement about this step is most accurate?
a) The step is termolecular; because [M] is effectively constant, the rate can be written as rate = k′[A][B].
b) The step is termolecular, and the rate law is rate = k[A][B][M].
c) The step is bimolecular, and the rate law is rate = k[A][B].
d) The step is unimolecular, and the rate law is rate = k[A].