Some metals, such as iron, can be oxidized to more than one oxidation state. Obtain the balanced net ionic equations for the following oxidation–reduction reactions, in which nitric acid is reduced to nitric oxide, NO.
a. Oxidation of iron metal to iron(II) ion by nitric acid.
b. Oxidation of iron(II) ion to iron(III) ion by nitric acid.
c. Oxidation of iron metal to iron(III) by nitric acid.
[Consider adding the a and b equations.]