Chapter 4, Problem 4.37QAP

Magnesium metal (a component of alloys used in aircraft and a reducing agent used in the production of uranium, titanium, and other active metals) is isolated from sea water by the following sequence of reactions: Mg2+(aq)+Ca(OH)2(aq)Mg(OH)2(s)+Ca2+(aq)Mg(OH)2(s)+2HCl(aq)MgCl2(s)+2H2O(l)MgCl2(l)electrolysisMg(s)+Cl2+Cl2(g) Sea water has a density of 1.026 g/cm3 and contains 1272 parts per million of magnesium a5 Mg2+(aq) by mass. What mass, in kilograms, of Ca(OH)2; is required to precipitate 99.9% of the magnesium in 1.00103 L of sea water?

A chemist dissolves a 1.497-g sample of a type of metal (an alloy of Sn, Pb, Sb, and Cu) in nitric acid, and metastannic acid, H2SnO3, is precipitated. She heats the precipitate to drive off the water, which leaves 0.4909 g of tin(IV) oxide. What was the percentage of [in in the original sample?

Ten mL of concentrated H3PO4 (91.7% by mass, d=1.69g/mL) was accidentally poured into a beaker containing 20.0 g of NaOH. Not all the NaOH was consumed. How many grams of NaOH were left unreacted? The equation for the reaction is H3PO4(aq)+3OH(aq)3H2O+PO43(aq)

Lead poisoning has been a hazard for centuries. Some scholars believe that the decline of the Roman Empire can be traced, in part, to high levels of lead in water from containers and pipes, and from wine that was stored in leadglazed containers. If we presume that the typical Roman water supply was saturated with lead carbonate, PbCO3 (Ksp = 7.4 1014), how much lead will a Roman ingest in a year if he or she drinks 1 L/day from the container?

4.49 Small quantities of hydrogen gas can be prepared by the following reaction: Zn(s)+H2SO4(aq)ZnSO4(aq)+H2(g) How many grams of H2 can be prepared from 25.0 mL of 6.00 M H2SO4 and excess zinc?

A sample of limestone weighing 1.005 g is dissolved in 75.00 mL of 0.2500 M hydrochloric acid. The following reaction occurs: CaCO3(s)+2 H+(aq)Ca2+(aq)+CO2(g)+H2O It is found that 19.26 mL of 0.150 M NaOH is required to titrate the excess HCI left after reaction with the limestone. What is the mass percent of CaCO3 in the limestone?

You are given a solid mixture of NaNO2 and NaCl and are asked to analyze it for the amount of NaNO2 present. To do so, you allow the mixture to react with sulfamic acid, HSO3NH2, in water according to the equation NaNO2(aq) + HSO3NH2(aq) NaHSO4(aq) + H2O() + N2(g) What is the weight percentage of NaNO2 in 1.232 g of the solid mixture if reaction with sulfa-mic acid produces 295 mL of dry N2 gas with a pressure of 713 mm Hg at 21.0 C?

Gold metal will dissolve only in aqua regia, a mixture of concentrated hydrochloric acid and concentrated nitric acid in a 3:1 volume ratio. The products of the reaction between gold and the concentrated acids are AuCl4-(aq), NO(g), and H2O. The equation for this reaction where HNO3 and HCl are strong acids is Au(s)+4Cl(aq)+4H+(aq)+NO3(aq)AuCl4(aq)+NO(g)+2H2O(a) What stoichiometric ratio of hydrochloric acid to nitric acid should be used? (b) What volumes of 12 M HCl and 16 M are HNO3 required to furnish the Cl- and NO3- ions to react with 25.0 g of gold?

When calcium carbonate is heated strongly, it evolves carbon dioxide gas. CaCO3(s)CaO(s)+CO2(g) 25 g of CaCO3 is heated, what mass of CO2would be produced? What volume would this quantity of CO2 (CU at STP?