A zeroth order reaction A = B has [A]0 = 0.012 M. After 5.0 min, [A] = .008M. What is the rate constant in units of Ms-1?

Question

Answer choices:

None of the above

k = -1.3 E-5 M/s

k = - 8.0 E-4 M/s

k = 1.3 E-5 M/s

k = 8.0 E-4 M/s

Answer 1

If this is a true zero order reaction, then the rate will be independent of the concentration of A, and we can write the rate equation as

rate = k

rate = k = 0.012 M - 0.008 M / 5 min

rate = k = 0.0008 M / min and converting this to M/s we have...

rate = l = 0.0008 M / 60 s = 1.3x10^-5 M/s