2. ParticleSymbolRelative Charge Relative Mass (proton = 1) Actual Mass (g) Electrone-e- 1-1/18409.11X10 -28 Protonp+p+ 1+11.67x10 -24 Neutronn0n0 011.67x10 -24

3.  Subatomic Particles  Proton  Positively charged particle  Equal to the Atomic Number  Electron  Negatively charged particle  Equal to # of protons (in a neutral atom)  Neutron  Uncharged particle (neutral)  Equal to Mass Number – Atomic Number

4.  Location of Subatomic Particles  Protons and neutrons are found in the nucleus  Electrons located in energy levels (orbitals) outside of the nucleus

5. C Carbon 6 12.011 Atomic Number Element Name Chemical Symbol Atomic Mass/Weight

6.  Atomic Number  Number of protons in atom  Number of electrons in atom  Mass Number (Atomic Mass rounded)  Number of protons plus neutrons  Chemical Symbol  One or two letters that stand for the element

7. 12 6 C protons=6 electrons = 6 neutrons=6 (12-6) atomic number mass number (rounded atomic mass)

8. Ions -atoms that have gained or lost electrons (negative particles) Anion: atoms that have gained electrons and have a negative charge Cation: atoms that have lost electrons and have a positive charge

9. Isotopes -Atoms that have the same number of protons, but different numbers of neutrons -different mass numbers Neon-2010 neutrons Neon-2111 neutrons Neon-2212 neutrons

10. (Average) Atomic Mass -isotopes occur in nature in a certain percentage (percent natural abundance) -the atomic mass of an element is a weighted average mass of atoms occurring in nature -see table 4.3

11. NamePercent Abundance Mass (amu)Average Atomic Mass Carbon-1298.8912.000 12.011 Carbon-131.1113.003 Carbon-14≤.0114.000 (.9889 * 12.000) + (0.0111 * 13.003) = 12.011