When the rate-controlling step is the first step, how is the molecularity of the rate-controlling step related to the overall reaction order?
a) Molecularity of the rate-controlling step equals the overall reaction order.
b) Molecularity of the rate-controlling step is greater than the overall reaction order.
c) Molecularity of the rate-controlling step is less than the overall reaction order.
d) Molecularity of the rate-controlling step is not related to the overall reaction order.