1. How atoms form compounds

2. What is a compound?
Compounds are pure substances that contain two or more elements.
Elements are pure substances made from one type of atom
COMPOUNDS HAVE DIFFERENT PROPERTIES THAN THE ELEMENTS THAT MAKE THEM UP
Chemical formulas are a short hand way of describing what is in a compound

3. IONS
Ions are an atom that is no longer neutral because it has gained or lost electrons
Positive ions lose electrons
Has more protons than electrons
Represented by the element’s symbol with a superscript plus sign (+)
Negative ions
Has more electrons than protons
Represented by the element’s symbol with a superscript negative sign (-)

5. Ionic Bonds
Ionic bonds require the transferring of electrons in order to form a chemical bond to make a compound
Two or more elements that are forced together is a bond

6. Ionic Compounds
Using the periodic table, you can figure out positive and negative ions
Using the number of valence electrons and Lewis Dot diagrams , you can figure out if they will combine
EXAMPLE: Group 1 with Group 17 form salts

7. Foldable Follow directions on pg 215 Info for Ionic bond: pg220-222
Info for Metallic bond: pg
HW: fill in metallic bond information
Tomorrow we will fill in the covalent bond information