Matter is the Stuff Around You. Matter is everything around you. Atoms and molecules are all composed of matter. Matter is anything that has mass and takes up space. If you are new to the idea of mass, it is the amount of stuff in an object.

pure Substances: Concept and Properties. ... The pure substance within chemistry is a very simple concept to grasp. Pure substances are defined as substances that are made of only one type of atom or only one type of molecule (a group of atoms bonded together). The measure of whether a substance is pure is known as purity.May 3, 2015

elements

Elements: a substance consisting of atom which all have the same number of protons i.e. the same atomic number.

Compounds: a pure substance composed of two or more different atom chemically bonded to one another

Mixture

mixture: a combination of two or more pure substance

there are two type of mixtures

homogeneous & heterogeneous

homogeneous: a solid, liquid or gaseous mixture that has the same proportions of its components throughout a given sample

heterogeneous: made of different substances that remain physically seperate

A suspension is a heterogeneous mixture in which solute-like particles settle out of a solvent-like phase some time after their introduction. We apply the word 'suspension' when particles are big enough to eventually settle. If the particles are too small to ever settle, they are said to form a colloid.

colloid: a homogeneous, noncrystalline substance consisting of large molecules or ultra microscopic particles of one substance dispersed through a second substance. Colloids include gels, sols, and emulsions; the particles do not settle and cannot be separated out by ordinary filtering or centrifuging like those in a suspension.