Oct. 3 – Ionic Formulas and Covalent Bonds

Learning Goals:

• Understand how ionic bonds form.
• Understand how covalent bonds form.

Success Criteria:

• You can write the formula for ionic compounds.
• You can explain how covalent bonds are formed between two non-metals.

Here's an interactive review of what we worked on yesterday:

http://www.bbc.co.uk/schools/gcsebitesize/science/add_edexcel/ionic_compounds/ionicact.shtml

Next we discussed the patters on the periodic table and how to figure out the ionic charges of each element.

Handout: Valence

Using these valences, we can figure out how many ions of each element are required to make an ionic compound.  I got some volunteers to come up and demonstrate using black and white beads as electrons and protons.  Then we discussed how you can use the crisscross method to figure out the same thing.

Handout: Writing formulas for ionic compounds

Finally we talked about covalent bonds.  Again, students came up to the front to demonstrate using beads as electrons.  In a covalent bond, the atoms don't lose or gain electrons, they share!

Handout: Covalent Bonds
Handout: Covalent Bonds Examples

If two hydrogen each share their electrons, then they will each have two, making a more stable molecule.  

Here's the example I showed in class of two oxygen forming a covalent bond with a carbon.

Homework: Complete the handouts.