2. Is Matter Around Us Pure
A pure substance consists of a single type of particles.
Pure substances are always homogeneous.
All the elements and compounds are pure substances because they contain only one kind of particles.
A pure substance cannot be separated into other kinds of matter by any physical process.
A pure substance has a fixed composition as well as a fixed boiling point and melting point.
Ex. Hydrogen, Oxygen, Copper, Gold, Silver.
Pure substances can be divided into two types.