00:01
So i'm drawing some lewis structures.
00:02
First for carbon tetrachloride.
00:05
Carbon has four valence electrons while chlorine has seven valence electrons.
00:13
So to draw the lewis structure, once you make all your dots, you're just going to play connect the dots.
00:18
Anytime you have an unpaired dot, go ahead and pair them up.
00:23
So there's our lewis structure.
00:25
For mgcl2, we're going to assume that we're drawing a...
00:33
Covalent bond.
00:36
Magnesium has two valence electrons.
00:40
There we go for it.
00:42
For ammonia, nh3, ammonia's got five valence electrons.
00:48
Our hydrogen only has one.
00:51
So we connect our dots there.
00:54
And now moving on to an ion.
00:57
In this case, we end up with six dots on the carbon, or on the oxygen, excuse me, four dots on the carbon and one on the hydrogen.
01:12
And because the thing has an overall negative charge, i need to add in one more dot somewhere.
01:16
I'm going to choose to add it to the top o.
01:19
I picked an o because o is more electronegative.
01:23
Now in this case, let's start lining things up.
01:26
Always do your h first, because it only needs one line.
01:29
The top o only needs one line to make the octet.
01:33
And now we can finish pairing up the other unpaired dots on the c and on the o...
