A sample of copper was pretreated and diluted to 500mL and portions of this solution were analyzed by measuring the absorbance of a copper (I) complex of 1, 20 phenanthroline using a standard addition technique. Use the following data to determine the % copper in the sample.
wt. of sample in 500 mL
4.275 g
Sample 0.00450 M Cu2+ Ligand H2O Absorbance
25mL 0mL 15mL 10mL 0.233
25 mL 8mL 15mL 2mL 0.545