00:01
Alright, so here we want to draw a loose structure that obeys the octet rule for br 03 minus, and then assign formal charges to each atom.
00:12
So how we calculate formal charge, formal charge is going to be the valence electrons minus the number of bonds minus loan pairs, or how many lone electrons there are.
00:38
So first what we're going to start off with is how many valence electrons we have to work with.
00:43
So from bromine we have 7, and from oxygen we have 6 times 3, and then from the charge we have 1 extra.
00:56
So we have 7 plus 18 plus 1.
01:04
It's 26 electrons.
01:06
So then we put bromine in the middle here, and we can draw a skeleton of oxygen atoms bound to it.
01:20
Move it over a little bit.
01:24
And so just from the skeleton, we've used up six electrons, now we have 20 left to work with.
01:30
So after you've made the skeleton, you can go ahead and fill in the outside electrons to fill up their valence.
01:39
Fill up the valence of the outer atoms.
01:42
So here, we've used up 18 electrons.
01:47
And then lastly, we can put a lone pair on the central atom if we have leftover electrons...
