Lewis Dots &
Ionic Bonding
Due Thursday 11/14/13
http://tinyurl.com/n2p2re7
Objectives
• Draw Lewis Dot Diagrams to represent the
number of valence electrons an atom has
• Write the chemical formula for ionic
compounds using the criss-cross method and
the Lewis Dot method
**Show all work for all problems!
Lewis Dot Diagrams
• AKA Electron Dot Diagrams
• Consists of
– Element symbol in the center
– 1-8 dots around the symbol representing valence
electrons
Lewis Dot Diagrams
• Steps:
1. Write the element’s symbol
2. Find the group #1A-8A. The group #1A-8A = Valence
Electrons = Lewis Dots
3. Put a Lewis dot on each side of the element first before
doubling up
Lewis Dot Diagrams
• Examples:
– Sodium
– Carbon
– Chlorine
Ionic Bonds
• Metal & nonmetal
- Metals lose electrons and form cations
- Nonmetals gain electrons and form anions
- This electrostatic attraction holds the atoms in an
ionic bond together
Ionic Bonds – Criss Cross
• Steps:
1. Find the common charge for each atom
2. The charge on the metal becomes the subscript
for the nonmetal
3. The charge on the nonmetal becomes the
subscript for the metal
- Overall net charge is 0
- Metal is written first in the formula
Ionic Bonds – Lewis Dots
• Steps:
1. Draw the Lewis Dot Diagram for the metal
2. Draw the Lewis Dot Diagram for the nonmetal
3. Transfer one electron at a time from the metal to an
available spot on the nonmetal
4. Continue until the metal has lost all of its electrons,
and the nonmetal has a full octet
Ionic Bonds – Practice 1
• Potassium & Chlorine
Ionic Bonds – Practice 2
• Magnesium & Phosphorous
Questions