| A | B |
|---|
| atom | smallest particle of an element |
| element | building block of matter |
| compound | two or more elements chemically combined in a specific ration |
| molecule | two or more atoms held together by chemical bonds |
| proton | positively charged particle found in the nucleus of an atom |
| neutron | neutral particle found in the nucleus of an atom |
| electron | negatively charged particle which orbits the nucleus of an atom |
| nucleus | the middle of the atom where the protons and neutrons are found |
| mean | the average of a set of number |
| median | the middle number in a set of numbers |
| range | the difference between the least and greatest numbers in a set |
| mode | the number which occurrs most in a set of numbers |
| periodic table of the elements | a reference tool used by scientists to get information about elements |
| CO2 | carbon dioxide |
| H2O | water |
| NH3 | ammonia |
| Fe2O3 | iron oxide - rust |
| NaCl | sodium chloride - salt |
