7B.5 7th edition

[Gisela F Ramirez 2H]

N2O5 decomposes by first order kinetics with a rate constant of 3.7*10^(-5) at 298K

For part a, find half life of N205 at 298K, what equation would I use?
For part c, how much time will elapse before the N2O5 concentration decreases from 0,0567 M to 0.0135 M? How would I solve this?

[ThomasLai1D]

For part a, you would use the equation [A] = [A]initial e^-kt, and plug in 1/2 [A] initial for [A].
For part c, you would use the same equation, but solve for t by plugging in the values for initial and final concentration into [A]initial and [A] respectively.