sulphur係molecule???

At room conditions, sulphur exists as S8 molecules. When sulphur is burned in air, the equation is then
S8(s) + 8O2(g) → 8SO2(g)

The above equation and all other equations involving S8 molecules are too complicated. Therefore, in writing chemical equations, the empirical formula of sulphur (i.e. S) is conventionally used instead of its molecular formula (i.e. S8) in order to make the equations simple. Therefore, the above equation can simply be written as follows:
S(s) + O2(g) → 8SO2(g)

Similar cases occur when writing chemical equation involving other elements which are made up of multi-atomic molecules. For example, in writing chemical equations, write P instead P4 (white phosphorus) or (P4)n (red phosphorus).