Chemistry 2710 Spring 2000 Quiz 1 solution

The rate of formation of P is the slope of the graph of p as a function of t. This slope can be found by linear regression. My calculator gives . The rate of reaction is therefore or .

There are two possible approaches to answering the question of whether this is truly an initial rate:

1. After 10s, only 3.2mmol/L of P has been formed. This corresponds to using up about 4.8mmol/L of A, less than 1% of the amount initially present. This is quite a small amount so the slope probably represents an initial rate.
2. If we plot p as a function of t, we get the following graph:

   

   The data fits a line very nicely, so we are still in the initial rate region.