For the reaction, A = B + C, the rate law is kA]. If it takes 80.0 seconds for 70.0% of a 10.0 gram sample of A to be transformed into products, what is the value of the rate constant?

a. 0.00450 s-1 b. 0.0290 s 1 c. 0.00530 s-1 d. 0.0150 s-1 e. 5.40 s-1

chemistry - DrBob222, Friday, February 17, 2012 at 10:06pm
rate = k(A) is first order.
Use ln(No/N) = kt. Substitute and solve for k.

B?

3 answers

Surely you didn't try this. Plug in those numbers and try again.
No = 10
N = ? if 70% has been transformed.
k ?
t = 80 sec.
I get the answer .01505 is that correct?
yes