| A | B |
|---|
| atom | the smallest part of an element that is still identified as that element |
| molecule | the smallest part of an element or compound, with at least one atom in an element, and two or more in a compoound |
| nucleus | the central portion of an atom containing protons and neutrons |
| proton | positively charged portion of an atom |
| neutron | non-charged portion in the nucleus of an atom |
| electron | negatively charged portion in the outer bands of an atom |
| element | a substance that cannot be separated into simpler parts by chemical means |
| Periodic Table of the Elements | a chart showing the relative size and weight of all the identified elements |
| atomic weight | the average weight of an atom of an element |
| atomic number | the number of proton's in an element's nucleus |
