17. Solution to Chemistry Problem

7. Mercury was determined by isotope dilution with substochnometric extraction.
To 10.00 ml of a solution containing mercury and other metals, 203Hg was added in an amount of m0. Hydroxylamine hydrochloride was then introduced to eliminate the interfering effect of oxidants that decompose dithizone, and mercury was extracted with a solution of dithizone in carbon tetrachloride. The activity of 1.00 ml of the organic phase was A2. A solution containing only 203Hg, as well as NH2OH•HCl and dithizone in the same concentrations, was extracted in parallel. The activity of 1.00 ml of the extract in this case was A1. Calculate the concentration (g/ml) of mercury in the initial solution using the following data:
Option 1 2 3
m0, μg 1.739 0.348 0.06957
A1, cpm 35.82 15.60 3.255
A2, cpm 13.61 9.02 2.290
SOLUTION FOR ALL THREE OPTIONS