| A | B |
| Democritus | first to talk about atoms, a particle too small to divide |
| Aristotle | believed you could always divide a piece |
| John Dalton | father of modern atomic theory |
| J. J. Thomson #1 | discovered electrons |
| Ernest Rutherford #1 | discovered the nucleus |
| Neils Bohr | believed electrons fell into specific orbits |
| Today's atomic theory | say electrons are found in clouds around the nucleus |
| atoms | smallest part of an element |
| J. J. Thomson #2 | cathode ray tube experiment |
| Ernest Rutherford #2 | gold foil experiment |
| electrons | negatively charged particles |
| nucleus | positively charged center of the atom |
| Dalton's Theory | atoms make up everything, form componuds, & atoms of each element are alike |