Homework 7/14

Page 151 #9-22

9. Active metals are more reactive than less active metals because more active metals have a higher chance of combining and forming compounds with other elements.

10. Silver would have been the easiest to process because of its lack of reactivity and its ability to remain separate from other metals and elements.

11. Most metals are more reactive than metals like silver, gold, and platinum because they are significantly more reactive.

12. A) This would be most likely to happen because calcium metal is more reactive than chromium metal which means that mixing calcium metal in chromium chloride would create a reaction, but mixing chromium metal in calcium chloride wouldn’t form a reaction.

13. B) This reaction is more likely to occur because zinc is more reactive than silver, so mixing the metal zinc into a silver solution would initiate a reaction.

14. A) Iron is more reactive than lead, so stirring a solution of lead nitrate with an iron spoon would cause a reaction that would cause the iron spoon to start to dissolve.

B) Pb²+(aq) + Fe(s) ---> Pb(s) + Fe²+(aq)

15. Oxidation is when an ion loses an electron and causes metal to become either a cation or aqueous equation. Reduction is the loss or gain of electrons to cause a balanced electrical charge and become a metal.

16. A) Au³+ + 3e^- ---> Au

B) V ---> V⁴+ + 4e^-

C) Cu+ ---> Cu²+ + 1e^-

17. A) Reduction

      B) Oxidation

      C) Reduction

18. A) Oxidized, loses 2 electrons, becomes a cation Zn²

B) Reduced, gains 2 electrons, becomes a solid Ni

C) Reduced, reaction is Zn

19. A) K^+ has been oxidized K loses an electron, becomes a cation/aqueous solution, K^+.

B) Hg has been reduced, Hg^2+ gains two electrons, becomes a metal/solid as Hg.

C) The oxidization, reaction is Hg^2+.

20. A) Al + Cr^3+ ---> Al^3+ + Cr

B) Mn^2+ + Mg ---> Mn + Mg^2+

21. A) Electrometallurgy is the use of an electrical current to add electrons to metal ions, therefor reducing them.

b. Pyrometallurgy is the combustion of metals and their ores as reducing the metal ions.

c. Hydrometallurgy is when ores and other metal-containing materials react in a water solution and leaches silver and gold from old mine tailings.

22. A) Electrometallurgy.

B) Pyrometallurgy