Type III Bonding Multiple bonds

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

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

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

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.

Like this:

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

NOW Count up the electrons each atom has:

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.

We would show things like this:

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

Like this:

And Finally:

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

WOW THIS IS FUN!!!!!!!!!