Ionic Bonding Chapter 15 Sections 1 and 2

Sodium is always willing to help. Alkali Metal

Valence Electrons  Electrons in the highest occupied energy level of an atom  Explain why atoms combine in the ratios that they do.  Determine the chemical properties

 The number of valence electrons is related to the group number This is so easy!

 Electron Dot structures –Shows the valence electrons as dots around the symbol

Octet Rule  The electron configurations of the Noble Gases usually involves 8 electrons –Atoms bond and form ions in an attempt to achieve a full octet –Ionic charge is associated with the valence electrons

The only absolute in chemistry is that there is always an exception!  Except He, compounds involving an odd # of electrons, Boron, Phosphorous, Beryllium and Sulfur  The transition elements will not achieve a Noble Gas configuration because of the “d” orbitals Space Ghost Says:

Ionic Bonds  The force of attraction between cations and anions. –Electrostatic attraction Positive charge must = Negative charge –Ionic formula shows the lowest whole number ratio of cations to anions –Electrons are given by the cation to the anion  Unit Cell –The smallest group of particles within a crystal that retains the shape of the crystal

Properties  Coordination number – the number of ions of opposite charge that surround the ion in a crystal  Na in NaCl = 6  Non-ductile  Non-malleable