Practice Problem 1

Use the data in the above table to calculate the rate at which phenolphthalein reacts with the OH^- ion during each of the following periods:

(a) During the first time interval, when the phenolphthalein concentration falls from 0.0050 M to 0.0045 M.

(b) During the second interval, when the concentration falls from 0.0045 M to 0.0040 M.

(c) During the third interval, when the concentration falls from 0.0040 M to 0.0035 M.

Answer

(a) 4.8 x 10^-5 M/s

(b) 4.2 x 10^-5 M/s

(c) 3.7 x 10^-5 M/s