00:01
It's a chemical bond that involves the sharing of electron pairs between atoms, and these electron pairs are known as bonding pairs.
00:07
So aside from bonding pairs, we can also have lone electron pairs, and so when we represent our covalent structures, we might use the lowest notation.
00:18
And what we need to take into account here is the valent electrons, because we know that the group number of the element, which correspond to its valent electron count, determines the reactivity of the molecule.
00:28
So for example, oxygen would like to bond to, say for example, two sodiums so that it can have a two minus charge by taking an electron from each of sodium, and then we'll have an ionic species, for example, there.
00:44
Here we're counting the valence electrons with some different covalent compounds to see which of them have even and which of them have odd counts.
00:53
So firstly, we've got no2, so we've got five.
00:57
Then we need to add two times six because nitrogen is group five and oxygen is group six.
01:04
So what we get is 17 valence electrons.
01:08
So here we have an odd count.
01:09
Next we have scl2.
01:13
So what we have is sulfur group six.
01:16
Add two lots of seven because chlorine is a halogen, so it's group seven.
01:21
And we have 20 valence electrons...