Children's toys and jewelry were assessed for their contamination by potentially toxic elements (PTE). This includes traces of As (74.92 g/mol), Cd (112.4 g/mol), Pb (207.2 g/mol), and Zn (65.39 g/mol) among others. The concentrations of these PTES were determined to characterize the subsequent health risks, and to possibly reinforce better legislation on the manufacturing of these products. A. If 365 ppb of Zn was observed, what is its equivalent in %(w/w)? B. A sample of plastic toy was treated resulting to a 500 mL solution. What is the concentration of Pb in ppm if 25 µg of Pb is found in the sample? C. A 250 mL stock solution of 1.5 M As standard was prepared. What volume (in mL) of As stock solution must you use to prepare 50 mL of 0.75 M As solution? D. If the treatment used HNO3 (p = 1.51 g/mL) as the solvent during dissolution, and the density of Cd is 8.7 g/mL, what is the concentration of Cd in molality if the amount of Cd found in a 250 mL solution was 24 mg?

Children's toys and jewelry were assessed for their contamination by potentially toxic elements (PTE). This includes traces of As (74.92 g/mol), Cd (112.4 g/mol), Pb (207.2 g/mol), and Zn (65.39 g/mol) among others. The concentrations of these PTES were determined to characterize the subsequent health risks, and to possibly reinforce better legislation on the manufacturing of these products. A. If 365 ppb of Zn was observed, what is its equivalent in %(w/w)? B. A sample of plastic toy was treated resulting to a 500 mL solution. What is the concentration of Pb in ppm if 25 µg of Pb is found in the sample? C. A 250 mL stock solution of 1.5 M As standard was prepared. What volume (in mL) of As stock solution must you use to prepare 50 mL of 0.75 M As solution? D. If the treatment used HNO3 (p = 1.51 g/mL) as the solvent during dissolution, and the density of Cd is 8.7 g/mL, what is the concentration of Cd in molality if the amount of Cd found in a 250 mL solution was 24 mg?

Chemistry

10th Edition

ISBN:9781305957404

Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Chapter1: Chemical Foundations

Section: Chapter Questions

Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...

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