Question

The herbicide dichlobenil (2,6-dichlorobenzonitrile, C7H3Cl2N) has a solubility of 18.0 mg/L by mass in water at 20 ∘C. The herbicide disintegrates with a half-life (first order) of 1.00 year. Suppose that 323 kg of dichlobenil is applied in the fields surrounding a 7.50-acre pond having an average depth of 3.00 ft. Suppose further that half of the dichlobenil permeates into the pond and that this happens within a few days. Assume that the density of the pond water is 1.00 g/mL.

The following conversion factors will be helpful:

1 acre = 43,560ft^2

1ft = 12 inch

1inch = 2.54 cm

1cm^3 = 1mL

1ft^3 = 28,317cm^3

After a few days, what will be the concentration of dichlobenil in the pond?

Answer 1

concentration of dichlobenil in the pond = 3.38 * 10^-5 M