Which one of the following sets of units is appropriate for a second-order rate constant?

A. s-1
B. mol L-1 s-1
C. L mol-1 s-1
D. mol2 L-2 s-1
E. L2 mol-2 s-1

C. L mol-1 s-1.

Explanation:

Hello,

In this case, a rate law has the following general form:

Whereas r accounts for the rate measured in M/s units, k is the rate constant whose units depends on the order of the reaction, C the concentration of the species in M units, contributing to the rate and x the order of the reaction.

In such a way, since in this case x equals two (second-order rate), the units of k turns out:

Which matches with C. L mol-1 s-1.

Best regards.