1. Ionic/Covalent Bonding Notes

2. Stable or Unstable?
An atom is only stable if it has a full valence shell
If an atom is stable, it will not bond
If an atom is not full, it will bond

3. Compounds
Compounds are formed when 2 atoms of different elements bond together.
Atoms bond to fill their valence shell
An atom will bond with an many atoms as it takes to fill its outer shell
Once the valence shell is full, that atom is stable

4. Types of Chemical Bonds
There are two types of chemical bonds:
Ionic Bonds
Covalent Bonds

5. Ionic Bonds Ionic bonds exist between a non- metal and a metal
When two atoms bond ionically, they gain/lose electrons
When an atom gains or loses an electron, it becomes an ion

6. Ions Ca +2 +2 +2 +2 +2 +2 +2 It has 2 valence electrons.
How many does it need to be stable?
8…so it can either lose 2 or gain 6. Which is easier?
Calcium is in group 2.
How many valence electrons does it have?
Which other elements would lose 2 electrons?
Group 1 18 2 13 14 15 16 17 3 4 5 6 7 8 9 10 11 12
Losing 2…if it loses 2 electrons, it becomes positive Ca +2 +2 +2 +2 +2 +2 +2

7. Ions +1 +1 +2 +3 +4 -3 -2 -1 +1 -2 +2 +3 +4 -3 -1 +1 -2 +2 +3 +4 -3 -1
Group 1 18 2 13 14 15 16 17 3 4 5 6 7 8 9 10 11 12 +1 +1 +2 +3 +4 -3 -2 -1 +1 -2 +2 +3 +4 -3 -1 +1 -2 +2 +3 +4 -3 -1 +1 +2 +3 +4 -3 -2 -1 +1 +2 +4 -3 -2 -1 +3 +1 +2

9. Ionic Bonds Properties of Ionic Compounds High melting point
Good conductor of electricity
Solid at room temperature

10. Covalent Bonds Covalent bonds exist between NONMETAL and NONMETAL.
Example: H2, H2O, NO3, CH4
Covalent bonds SHARE electrons.
Shared electrons don’t belong to either atom.

13. Covalent Bonds Properties of Covalent Compounds Low melting point
Poor conductor of electricity
Liquid or Gas at room temperature