1. (a) We assume that chloride has valence -1 then aluminum chloride has
aluminum 3+.
(b) If we assume that Fe has valence 2+ in FeS then S is 2- in that compound. We assume that oxygen has valence 2- in sulfate then S has valence 6+ in SO_4^{2-}. Similarly, N has valence 5+ in nitrate ion, NO_3^{-}.
4. "A product favored oxidation reduction reaction has:
(b) a negative 
and a positive E^o. This is because 
.
Statement (c) is correct, but favors reactants because > 0.
18.
(a) 
(b) 
(c) 
28. 
= -(2)(96,500 Coul)(2.91 V) = -1,121.4kJ/mol
41. 
The electrochemical potential for all concentrations 0.015M is:
= -(2)(96.5)(0.838) = -161.8 kJ/mol
44. Click here for some std potentials in alphabetical order
(a) 
gives K = 6.0 x 10^{7}
45.
(b) 
gives K = 3.5 x 10^{15}
46. 
Ms(Au) = 196.97. 1g gold = 0.00508 moles. It takes 3x0.00508 = 0.01523 Faradays to produce 1 g of Au(s) from the ion. The number of Coulombs is therefore 0.01523 moles x 96,500 C/mol = 1,470 Coulombs. amp = Coul/sec, or sec = Coul/amp. The time taken to plate gold will be 1,470 Coul/2 amp = 735 sec.