| A | B |
|---|
| matter | anything made up of atoms that has mass and takes up space |
| solid | a substance that has a definite shape and definite volume |
| liquid | a substance that has a definite volume, but no definite shape |
| gas | a substance without a definite volume or shape |
| physical property | a feature of matter that can be observed or measured |
| mass | the amount of matter something has for its volume |
| density | how much mass something has for its volume |
| volume | the amount of space something takes up |
| conductivity | the ability of a metal to allow electricity or heat to pass through it |
| insulation | the ability to stop most electricity or heat from passing through |
| physical change | a change that begins and ends with the same kind of matter |
| chemical change | a change that begins with one kind of matter and ends with another kind of matter with different properties |
| boiling point | the temperature at which a liquid changes to a gas |
| freezing point | the temperature at which a liquid changes to a solid |
| melting point | the temperature at which a solid change to a liquid |
| atom | the smallest bit of matter |
| proton | a particle in an atom's nucleus that has a positive electrical charge |
| neutron | a particle in an atom's nucleus that has no electrical charge |
| electron | a particle surrounding an atom's nucleus that has a negative electrical charge |
| atomic theory | the idea that everything is made of small particles |
| molecule | two or more atoms joined together |
| element | matter made of only one kind of atom |
| compound | matter made of two or more elements |
| mixture | a combination of two or more kinds of matter in which the properties of each kind of matter do not change |
| solution | two or more kinds of matter mixed together so evenly that they cannot be separated easily |
| dissolve | to break up into tiny bits and spread out |
| chemical reaction | the process by which a chemical change takes place |
| reactant | the matter at the beginning of a chemical change |
| product | the new matter formed at the end of a chemical change |
