Everything that makes up the world around you; anything that has mass and volume.

The amount of matter in an object.

The amount of space an object takes up.

The amount of mass in a certain volume of material; found by dividing the mass of an object by its volume.

A property that can be observed without changing the identity of a substance.

A change in size, shape, or state, without forming a new substance. 

A mixture of one substance dissolved in another so that the properties are the same throughout.