click below
click below
Normal Size Small Size show me how
Chemistry
Ch. 4 Review
| Question | Answer |
|---|---|
| atom | smallest particle of an element that retains its identity in a chemical reaction |
| Democritus's Atomic Philosophy | believed that atoms were indivisible and indestructible |
| Dalton Atomic Theory | transformed Democritus's ideas on atoms into a scientific theory |
| Thomson | discovered the electron. |
| electrons | are negatively charged subatomic particles |
| Ernest Rutherford | proposed that the atom is mostly empty space, thus explaining the lack of deflection of most of the alpha particles |
| nucleus | is the tiny central core of an atom and is composed of protons and neutrons |
| mass number | total number of protons and neutrons in an atom |
| atomic number | is the number of protons in the nucleus of an atom of that element |