| A | B |
|---|
| atom | smallest piece of substance that can't be broken down and still be that substance |
| proton | positively charged particle in the nucleus |
| electron | negatively charged particle surrounding the nucleus |
| neutron | neutrally charged particle in the nucleus |
| nucleus | center of the atom |
| radioactive element | substance that shoots off part of its molecules |
| physical change | boiling, breaking, melting, freezing, can go back to original substance |
| chemical change | baking, fried egg, new molecules, can't go back to original substance |
| atomic number | number of protons, little top number |
| mass number | number of protons + neutrons, little bottom number rounded to nearest whole number |
| the atomic number of carbon | 6 |
| the mass number of carbon | 12 |
| symbol | what you write for an element |
| formula | what you write for a compound |
| compound | two or more different kinds of atoms bonded together in a molecule |
| element | a substance with only one kind of atom |
| mass | amount of matter in an object |
| density | mass per volume |
| three important physical properties of matter | mass, density, volume |
| specific gravity | water=1.0 |
