6. Solution to Chemistry Problem

8. A sample of bronze weighing m g was dissolved in nitric acid, the solution was transferred to a 25.00 ml measuring flask, neutralized with ammonia and brought up to the mark with water. To determine beryllium, 5.00 ml of the resulting solution was taken, EDTA was added to mask interfering elements, acetate buffer and titrated with a 0.1000 M (K = 0.913) solution of disubstituted ammonium phosphate labeled with radioactive 32P. The titration results are given below:
V(Na2HPO4), ml 1.00 2.00 3.00 4.00 5.00 6.00 7.00
A, cpm at m=0.8120 g 60 60 60 60 60 840 1600
A, cpm at m=0.7981 g 50 50 50 50 300 1200 -
A, cpm at m=0.9002 g 60 60 60 60 180 500 800
Determine the mass fraction (%) of beryllium in bronze.
Solution for option 1