Oxidation of Elements and Their Reactions
Which element is oxidized and which element is reduced in each of the following reactions?
a. N2(g) + 3H2(g) => 2NH3(g)
b. 3Fe(NO3)2(aq) + 2Al(s) => 3Fe(s) + 2Al(NO3)3(aq)
c. Cl2(g) + 2NaI(aq) => I2(aq) + 2NaCl(aq)
d. PbS(s) + 4H2O2(aq) => PbSO4(s) + 4H2O(l)