Homework #4

#9-22 (p.151)

9) Active metals are more reactive than less active metals. Active metals are more likely to combine and form compounds with other elements which makes them more difficult to process and refine.

10)

11)  This is because metals are reactive and combine with other elements.


12) A reaction between calcium metal with chromium(III) chloride would more likely occur because calcium metal is more reactive than chromium metal.

13)  Zinc in a silver solution would cause a reaction because the more reactive material is in a less reactive solution.

14)

a. This is because the spoon would cause a reaction.
b. Pb^2+(aq) + Fe(s) ---> Pb(s) + Fe^2(aq)

15) Oxidation is the loss of one or more electrons that causes a metal to become a cation/aqueous solution. Reduction is the 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. Zinc
b. Nickel
c. Zinc

19)
a. Potassium
b. Mercury
c. Mercury

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

21)
a. Electrometallurgy is the use of electricity.
b. Pyrometallurgy is the use of heat.
c. Hydrometallurgy is the use of water.

22)
a. Electrometallurgy.
b. Pyrometallurgy