## 15.39a - "0.37[A]o"

$\frac{d[R]}{dt}=-k[R]^{2}; \frac{1}{[R]}=kt + \frac{1}{[R]_{0}}; t_{\frac{1}{2}}=\frac{1}{k[R]_{0}}$

Chris Freking 2G
Posts: 60
Joined: Fri Sep 28, 2018 12:29 am

### 15.39a - "0.37[A]o"

15.39 Determine the time required for each of the following second-order reactions to take place: (a) 2 A -> B + C, for the concentration of A to decrease from 0.10 mol/L to 0.080 mol/L, given that k = 0.015 L-1 mol min for the rate law expressed in terms of the loss of A.

In the 6th edition solutions manual, [A]t is calculated as 0.055molA/L, but then calculated to 0.37[A]o.

Why is this information relevant if we only need and already have [A]t, [A]o, and k to solve for t in the second order integrated rate equation?

Posts: 72
Joined: Fri Sep 28, 2018 12:19 am

### Re: 15.39a - "0.37[A]o"

i am also confused by this.. the concentrations used to find that answer of part a is from the information given in part b