A second-order reaction has a rate constant k of 0.004501(M s). If the initial concentration is 1.50 M, what is the concentration after 2.00 minutes?

Question

A second-order reaction has a rate constant k of 0.004501(M s). If the initial concentration is 1.50 M, what is the concentration after 2.00 minutes? 

Answer 1

The units given for the rate constant are not correct for a second order rate constant. The units should be

M^-1s^-1. Perhaps you just copied in wrong. At any rate ...

rate = k[X]²

rate = (0.004502)(1.50)²

rate = 0.01013 M s^-1

2.00 min x 60 sec/min = 120 sec

120 sec x 0.01013 M/sec = 1.215 M

Concentration remaining = 1.50 M - 1.215 M = 0.284 M