<P> A chemical substance , also known as a pure substance , is a form of matter that has constant chemical composition and characteristic properties . It can not be separated into components by physical separation methods , i.e. , without breaking chemical bonds . Chemical substances can be chemical elements , chemical compounds , ions or alloys . </P>
<P> A chemical substance , also known as a pure substance , is a form of matter that has constant chemical composition and characteristic properties . It can not be separated into components by physical separation methods , i.e. , without breaking chemical bonds . Chemical substances can be chemical elements , chemical compounds , ions or alloys . </P>
what sample of matter is classified as a substance
what sample of matter is classified as a substance
alloys ions chemical compounds chemical elements
alloys ions chemical compounds chemical elements