Isotopes different forms of same element. Same number of Protons, but different mass Radioactive Isotopes
Electrons (e - ) Arranged in shells Valence Hydrogen (H) Atomic number = 1 Electron Carbon (C) Atomic number = 6 Nitrogen (N) Atomic number = 7 Oxygen (O) Atomic number = 8 Outermost electron shell (can hold 8 electrons) First electron shell (can hold 2 electrons) Reactivity
Chemical Bonding – Ionic Bonds Form between Ions of opposite charge NaCl –One atom gives up e - (cation). –One atom recieves e - (anion). –Results in filled outer shells for both.