| A | B |
|---|
| Atoms of each element are ___ from the atoms of all other elements | different |
| Dalton theorized that atoms are indivisible, but the discovery of ____ particles changed this thoery | subatomic |
| electrons have a charge that is | negative |
| protons have a charge that is | posotive |
| neutrons have a charge that is | neutral |
| protons and neutrons are found in what part of the atom | neucleus |
| discovered the nucleus of an atom | rutherford |
| the nucleus' charge is | posotive |
| what occupys the most volume of an atom | electrons |
| what occupies the least amount of volume in an atom | nucleus |
| the atomic number is the number of | protons |
| the number of protons and ____ in an atom are equal | electrons |
| the mass number is the number of | protons and neutrons |
| Atoms of the same element are identical in most espects, but they can differ in the number of | neutrons |
| Atoms that hvae the same number of protons but different mass number are called | isotopes |
| the ___ of an element is weighted average of the masses of the isotopes of that element | atomic mass |
| an atom of teh sulfer-32 isotope contains ___ protons and neutrons | 16 |
| each of the three known isotopes of hydrogen has ___ protons(s) in the nucleus | 1 |
| the most common hydrogen isotopes has ____ neutrons | no |
| the atomic mass of hydrogen is | 1 |
| Sir Joseph Thompson | used a cathode ray tube and found the e-; 1197 |
| R.A. Millikan | determined mass of electron from Thomas' experiment |
| Rutherford | Gold Foil experiment- found nucleus; 1911 |
| Sir James Chadwick | found neutron; 1932 |
