To study the effect of heat on a few chemical substances.
Heat a little amount of each substance in a test tube and apply a glowing splint to the gas coming out.
Observe that in all cases the gas re-lights a glowing splint; write down other observations you make in each case, and describe the residues.
All the substances listed give oxygen on heating, but they do not do so at the same rate. Oxygen mixture, potassium permanganate and hydrogen peroxide would provide a good source of oxygen.