This is the culmination of the work of 5 eminent physicists, Dalton, Thomson, Rutherford, Bohr and Chadwick.Their work basically culminates in the ideas above and the important fact that an atom consists of:A nucleus containing protons and neutrons surrounded byElectrons in orbital around the nucleus.3. Atomic Number = Number of Protons4. Atomic Mass = Protons + Neutrons 5. Atomic Mass – Protons = Neutrons 6. Atomic Number – Atomic mass = Neutrons7.Protons = Electrons8. Valence electrons are electrons on outermost shell of an atom.5. Ionic bonds happen by transfer of electrons from one atom to another, usually between metals and nonmetalsHalite = NaCl Na | Cl | 1 Valence Electron | 7 Valence Electrons | Oxidation Number +1 | -1 |
***An oxidation number is a positive or negative number that indicates how many electrons ***an atom has gained, lost, or shared to become stable. Oxidation Numbers * Ionic bond: Halite | | | | | | | | | | Covalent Bonds: Where two atoms share an electron to get a total of 8 valence electrons, usually nonmetals
Compound: 2 or more atoms that are chemically bonded together. Minerals are compounds Quartz is SiO2
8. Study periodic symbol and elements
9. Know how to interpret chemical formulas, for example what does NaCl mean? Sodium Chloride, Halite, or table salt.
10. Isotopes: Simply put, isotopes are atoms with the same number of protons but different numbers of neutrons. Uranium 235 and Uranium 238 are isotopes of uranium. Because only the number of neutrons is involved, all isotopes are chemical elements, not molecules or compounds
Formation of the Solar System 1. The nebular theory was