Henry Edward Armstrong FRS FRSE (Hon) was a British chemist. Although Armstrong was active in many areas of scientific research, such as the chemistry of naphthalene derivatives, he is remembered today largely for his ideas and work on the teaching of science. Armstrong's acid is named for him.

Benzene is an organic chemical compound with the molecular formula C6H6. The benzene molecule is composed of six carbon atoms joined in a planar hexagonal ring with one hydrogen atom attached to each. Because it contains only carbon and hydrogen atoms, benzene is classed as a hydrocarbon.