Homework #17

2SBS #9-18


9. Active metals are more reactive than less active metals. Because of this, more active metals are more likely to combine and form compounds with other elements, where as less active metals tend to remain separate. 


10. Silver would have been the easiest to process because of its lack of reactivity. Since silver remains separate from other metals and elements, it would be quite easy to process. 


11. Since most metals are more reactive than metals like silver, gold, and platinum, their reactivities tend to make them combine with other elements and form compounds, or minerals. 


12. a. A reaction between calcium metal with chromium(III) chloride would more likely occur. Calcium metal is more reactive than chromium metal; therefore, putting calcium metal in chromium chloride would create a reaction, where as putting chromium metal in calcium chloride would not form any reaction. 


13 . b. Since zinc is much more reactive than silver, which is barely reactive, putting the metal zinc into a silver solution would cause a reaction; a reaction occurs between a more reactive metal and a less reactive solution. 


14. a. Since iron is more reactive than lead, stirring a solution of lead (II) nitrate with an iron spoon would cause a reaction, and the iron spoon would most likely begin to dissolve. 
      b. Pb^2+(aq) + Fe(s) ---> Pb(s) + Fe^2+(aq)

15. Oxidation is the apparent loss of one or more electrons that causes a metal to become a cation/aqueous solution. Reduction is the apparent gain of one or more electrons that causes a cation/aqueous solution to balance its electrical charge and become a metal. 

16. a. Au^3+ + 3e^- ---> Au

      b. V ---> V^4+ + 4e^-
      c. Cu+ ---> Cu^2+ + 1e^-

17. a. reduction.

      b. oxidation.
      c. reduction. 

18. a. Zn^2+ has been oxidized. Zn loses two electrons to become a cation/aqueous solution, Zn^2+. 

      b. Ni has been reduced. Ni^2+ gains two electrons to essentially rebalance its charge and become a metal/solid as Ni.
      c. The reducing agent in this reaction is Zn.


19. ?


20. a. Al + Cr^3+ ---> Al^3+ + Cr
b. Mn^2+ + Mg ---> Mn + Mg^2+

21. I don't know

22. a. Electrometallurgy.
b. Pyrometallurgy or find the metal uncombined.