A 25.0 mL sample of waste water is obtained to analyze for Pb^(2+) ions. This sample is evaporated to dryness and redissolved in 2.0 mL of H_(2)O, mixed with 2.0 mL of a buffer solution and 2.0 mL of a solution of dithizone then diluted to 10.0 mL. The absorbance of the coloured Pb^(2+) dithizone complex is compared with the Beer-Lambert plot below.The absorbance of a proton of the final solution is 0.13. What is the concentration of Pb^(2+) ions in the waste water in ppm ?

A 25.0 mL sample of waste water is obtained to analyze for Pb^(2+) ion

1.	A 25.0 mL sample of waste water is obtained to analyze for Pb^(2+) ions. This sample is evaporated to dryness and redissolved in 2.0 mL of H_(2)O, mixed with 2.0 mL of a buffer solution and 2.0 mL of a solution of dithizone then diluted to 10.0 mL. The absorbance of the coloured Pb^(2+) dithizone complex is compared with the Beer-Lambert plot below.The absorbance of a proton of the final solution is 0.13. What is the concentration of Pb^(2+) ions in the waste water in ppm ?
Answer» `2.9` `7.2` 18 36 Answer :A