1. Using the data table, estimate the half-life of the reaction; select two points, one with an absorbance value that is about half of the other absorbance value. The time it takes the absorbance (or concentration) to be halved is known as the half-life for the reaction. Also calculate the half-life from the rate constant, k, using the appropriate concentration-time formula.

Time(s)	0	10	20	30	40	50	60	70	80
Abs	0.4710833	0.37263414	0.29756946	0.23807216	0.19044029	0.15366289	0.12493874	0.09963287	0.08512818

90	100	110	120
0.07262964	0.05898576	0.05207638	0.04431225