When wax is burnt (in the form of a wax candle), then water and carbon dioxide are formed. This shows the "change in state" characteristic of reactions.
Name the products formed when :
(a) wood is burnt in the absence of air.
(b) bone is heated in the absence of air.
(c) diamond is burnt in air at 900∘C.
(d) graphite is subjected to high pressure and 3000∘ C temperature.