| A | B |
|---|
| atom | tiny particle that makes up all matter |
| proton | a particle in the nucleus of an atom that has a positive charge |
| electron | a particle with a negative electric charge that moves around the nucleus of an atom |
| element | matter made of one kind of atom |
| compound | substance formed from the chemical combination of atoms of different elements |
| physical property | a characteristic that can be observed without a substance being changed to a different substance |
| chemical property | a characteristic that can be observed when a substance changes to another substance |
| physical change | a change in size, shape or state of matter; does not cause a new substance to be formed |
| chemical change | the formation of a new substance with different chemical properties |
| chemical reaction | the process of chemical change |
| formula | a group of symbols used to show the elements in a compound |
| periodic table | a chart used by scientists to classify elements |
