# Question #67cea

##### 1 Answer

Jul 14, 2017

Here's what I get.

#### Explanation:

**(a) Exponential decay model**

The rate law for a first-order reaction is

where

Now,

(I had to write the half-life as

In this problem,

So, your exponential expression is

**(b) Graph**

I plotted the graph in Excel:

It looks like BAC = 0.075 mg/mol at 3.0 h.

I would guess that BAC = 0.08 mg/mL at 2.9 h.

You can drive home at about 02:55.