1. Mr. Gardner 7th Srade Science
Section 3: Ionic Bonds
Mr. Gardner 7th Srade Science

2. Key Concepts What are ions, and how do they form bonds?
How are the formulas and names of ionic compounds written?
What are the properties of ionic compounds?

3. Key Terms Ionic Polyatomic Ionic compounds Chemical formula Subscript
Crystal

5. Ions and Ionic Bonds
Almost every atom feels better when they have 8 electrons in their valence shell.
Ions: A group of atoms that have an electric charge.
Either positive or negative
When an atom looses an electron it becomes positive
When an atom gains an atom
Polyatomic Ions
Ions made of more than one atom.

6. Ionic Bonds

7. Chemical Formulas and Names
Chemical Formula: A combination of symbols that shows the ration of elements in a compound.

8. Formulas of Ionic Compounds
When ionic compounds form, the ions come together in a way that balances out the charges on the ions. The chemical formula for the compounds reflects this balance.
Subscript: tells you the ration of elements in the compound.

9. Naming Ionic compounds
The name of the positive ion comes first, followed by the name of the negative ion (usually).
NaCl = Sodium Chloride
MgCl2 = Magnesium Chloride
Usually ends in ide
Polyatomic ions are different:
Usually ends in ate
NH4NO3 = Ammonium Nitrate

10. Properties of Ionic Compounds
Ionic Crystals
Ions form an orderly, three dimensional arrangement called Crystals.
High Melting points
Electrical Conductivity