1. Type III Bonding
Multiple bonds

2. Recall that Type III bonds are:
Covalent bonds (sharing of e- between nuclei)
Atoms close to each other on periodic table
Non-metals bonding with other non-metals

3. Where do we start again?
Start by counting up the total # if valence e- all the atoms involved have
Arrange the e- so that each atom reaches the desired pseudo octet configuration through sharing

4. What do you do when:
They do not seem to have the right # of e- to form that octet for each atom?
Move the electrons to create multiple bonds

5. Example O2
Each oxygen atom has 6 valence electrons – which gives us 12 total electrons to work with
Start by arranging the atoms involved so that there is a single pair of shared electrons between the atoms and that each atom has an octet.

6. Like this:

7. But wait, that is too many electrons!
That is correct. We only can have 12 electrons total, but here we have 14
So here we move electrons to create multiple bonds

8. NOW
Count up the electrons each atom has:

9. HEY The oxygen on the left has 10 electrons – what now?
This allows us to remove 2 electrons from the oxygen that has a surplus – so that each atom has an octet, and we have 12 total electrons involved.

10. We would show things like this:

11. What about N2 1) 10 total electrons (5 valence e- each)
2) Draw it out with a single bond and octet for each
3) Move electrons to create multiple bonds and eliminate surplus electrons

12. Like this:

13. And Finally:

14. What about HCN?
10 total electrons
Recall that H is happy with 2

15. WOW
THIS IS FUN!!!!!!!!!