​Definition of matter

• ​Matter is anything that has mass and takes up volume.

• ​To be able to determine if a specific thing is a matter or not ask yourself: 1)Does it have mass? 2)​Does it take up space?

• ​If the answers are yes then this is an example of matter.

​Physical vs Chemical changes

• ​Physical changes only change the appearance of a substance, not its chemical composition.

• N.B Physical changes are reversible​

• ​Chemical changes cause a substance to change into an entirely new substance with a new chemical formula.

• ​N.B Chemical changes are irreversible.