WebChemistry is the scientific study of the properties and behavior of matter. It is a physical science within the natural sciences that studies the chemical elements that make up matter and compounds made of atoms, molecules and ions: their composition, structure, properties, behavior and the changes they undergo during reactions with other substances.
Web化學元素(英語: chemical element ),常简称元素(英語: element ),是一百多种基本的金属和非金属纯物质,也是構成物質的基本單位,不能直接用化學方法分解。 同一種化學元素是由質子數相同的原子組成,用一般的化学方法不能使之分解。 所有化學物質都是由元素組成,即任何物質都包含元素。