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Phys, Science Chap 4
Vocabulary
| Question | Answer |
|---|---|
| Electron | A subatomic particle that has a negative charge. |
| Nucleus | An atom's central region,which is made up of protons and neutrons. |
| Proton | A subatomic particle that has a positive charge and that is located in the nucleus of an atom. |
| Neutron | A subatomic particle that has no charge and that is located in the nucleus of an atom. |
| Atomic Number | The number of protons in the nucleus of an atom |
| Mass Number | The sum of the numbers of protons and neutrons in the nucleus of an atom. |
| Isotope | An atom that has the same number of protons (or the same atomic number) as other atoms of the same element do but that has a different number of neutrons (and thus a different atomic mass). |
| Unified Atomic Mass Unit | A unit of mass that describes the mass of an atom or molecule; it is exactly 1/12 the mass of a carbon atom with mass number 12 (symbol, u) |
| Mole | The SI base unit used to measure the amount of a substance whose number of particles is the same as the number of atoms of carbon in exactly 12g of carbon-12. |
| Orbital | a region in an atom where there is a high probability of finding electrons. |
| Valence Electron | An electron that is found in the outermost shell of an atom and that determines the atom's chemical properties. |
| Photon | A unit or quantum of light. |