12.1What are the oxidation numbers of the different types of atoms
in potassium permanganate, KMnO4? In manganese dioxide,
manganous sulphate, MnSO4? Is the manganese oxidised
or reduced, in going from manganese dioxide to potassium permanganate?1
13.1What are the oxidation numbers of the metal atoms in potassium chromate,
K2CrO4? In potassium dichromate, K2Cr2O7?
In chromous chloride, CrCl2? Is the chromium atom oxidised,
or reduced, in going from dichromate to chromous chloride?1
14. What is the difference between the oxidation number method and
the half-reaction method for balancing oxidation-reduction equations?
15. What three quantities must be accounted for in successfully
balancing an oxidation-reduction equation? Which quantity is balanced
last when using the half-reaction method, but first when
using the other method?
16. In what sense do the principles of conservation of mass and
conservation of energy fail when we turn from chemical to nuclear
reactions? Why? What new conservation principle can be used instead?
17. How do the energies involved in a typical chemical reaction
and a typical nuclear reaction compare?