hildren'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 Cd was observed, what is its equivalent in %(w/w)? B. A sample of plastic toy was treated resulting to a 1000 ml solution. What is the concentration of As in ppm if 65 µg of As is found in the sample? C. A 250 mL stock solution of 1.5 M Pb standard was prepared. What volume (in mL) of Pb stock solution must you use to prepare 50 mL of 0.15 M Pb solution? D. If the treatment used HNO3 (p = 1.51 g/mL) as the solvent during dissolution, and the density of Zn is 7.1 g/mL, what is the concentration of Zn in molality if the amount of Cd found in a 250 mL solution was 48 mg?

hildren'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 Cd was observed, what is its equivalent in %(w/w)? B. A sample of plastic toy was treated resulting to a 1000 ml solution. What is the concentration of As in ppm if 65 µg of As is found in the sample? C. A 250 mL stock solution of 1.5 M Pb standard was prepared. What volume (in mL) of Pb stock solution must you use to prepare 50 mL of 0.15 M Pb solution? D. If the treatment used HNO3 (p = 1.51 g/mL) as the solvent during dissolution, and the density of Zn is 7.1 g/mL, what is the concentration of Zn in molality if the amount of Cd found in a 250 mL solution was 48 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...

See similar textbooks

Similar questions

Heavy metal sulfides like CdS and PbS are often significant components of mine tailings (the piles of waste and low-grade ores discarded by a mining operation). While these sulfides are quite insoluble in water (Ksp of CdS = 1 E -27, Ksp of PbS = 3 E -28), over the years rainwater and snowmelt can slowly dissolve small amounts of these heavy metals, washing them into streams and other natural waters. If these mine tailings are located in an area that is impacted by acid rain, would you expect heavy metal dissolution into natural waters to increase or decrease? Use chemical reactions to justify your answer.
Balance the following equation by filling the gaps with appropriate numbers. [5] C +....... [2] SO2 →......... [1] CS2 +............. [4] CO
Write out the nuclear energy configuration (energy configuration of protons and neutrons in the nucleus, nuclear orbitals) of Calcium-40 and use it to explain why Ca-40 is an exceptionally stable and the most common isotope of Ca.
What are the products obtained from the reaction of H2SO4(aq) and Mg(OH)2 (aq)?
• Glass is formed by heating sand (silica) with sodium carbonate or calcium carbonate. The molten liquid cools into a hard and transparent material. The addition of metal oxides alters the color of the resulting glass. • Beta-titanium is composed primarily of titanium and heat-treated with a mix of metals such as aluminum and vanadium. The resulting material has high strength and corrosion resistance, and is used in dental implants and aircraft parts. • Iron (II) sulfide is formed by heating metallic iron and elemental sulfur. This results in the formation of a non-magnetic all-black mineral. Given the three statements above, which of the following is TRUE? Select one: O a. Only one material is classified as a homogeneous mixture. O b. Only one material is classified as a pure substance. All materials are classified as homogeneous mixtures. O c. O d. All materials are classified as pure substances. می
A 20.0-gram sample of impure NaClO3 produces 4.72 L of oxygen (STP). What is the percentage purity of the NaClO3? 2NaClO3(s) -> 2NaCl(s) + 3O2(g) 74.8 % 81.0 % 83.0 % 85.0 % 87.0 %
For some questions you will need to use the special periodic table attached in the images below! Treat Je, Qu, Ap, and Bg as NONMETALS! A) Enter the balanced chemical equation for the reaction of 2-bogusopropanoic acid with KOH. B) Enter the balanced equation for the ionization of 2-bogusopropanoic acid in water.
How and why can two lethal elements combine to form an essential compound for health
9) a.)What is the name of the compound formed when iron reacts with oxygen? Iron oxide b.)Since iron is present as Fe3+ in this compound, what is the formula?
Give one event that carbon monoxide poisoning may happen.
Hydrazine, N2H4, can be used as fuel to orient and maneuver spacecraft. The energy used to do so is obtained by reacting the hydrazine with dinitrogen tetroxide to form nitrogen gas and water vapor. Write and balance the chemical equation for this reaction.The spy satellite US-193 had 453 kg of hydrazine on board when it was destroyed. What mass of dinitrogen tetroxide would have had to be on board in order to completely react with the hydrazine? This reaction is a redox reaction. Assign oxidation states to each atom in the reaction,identify what is oxidized, what is reduced, the oxidizing agent, and the reducing agent. Answer in full please.
What is the molar mass of ginkgolide B (C 20H 24O 10), a complex compound isolated from the ginkgo tree? Extracts of the roots, bark, and seeds of the ginkgo tree comprise the most widely taken herbal supplements used today.