Chemical Bonding and Molecular Structure Chapter 12 Sec 12.1 - 12.7 Chapter 12 Sec 12.1 - 12.7
Review… Chemical bonds involve electrons Specifically, valence electrons (outer s and p orbitals) These electrons are transferred or shared in a molecule
Using Electronegativity: Large ∆EN = Ionic bond Medium ∆EN = Polar Covalent bond Small ∆EN = Non-polar Covalent bond Distance between location of elements on Periodic Table corresponds closely with ∆EN.
Polarity Bonds (and molecules) are “polar” if there is an unequal sharing of electrons
Means “Partial Charge” A - indicates a partial negative charge (near the more electronegative atom While + is a partial positive charge
Rules for Drawing Lewis Structures: 1.Find the sum of all valence electrons of atoms in the molecule 2.Use a pair of electrons to represent a bond between two atoms 3.Rearrange remaining electrons to satisfy octet rule (or duet rule for H)
For an Ionic Compound: Note that Potassium loses its valence electron to chlorine. The brackets indicate a negative charge around the chloride ion.