00:01
Alright, so chapter two, problem three is asking us what information exactly does the periodic table provide? so i've drawn off a small periodic table here, and immediately we can see that in any given, say, element, we're going to get the atomic symbol here, the atomic number here, and there's also to be the mass.
00:34
So for this particular one, it would be about 32, and 0 .07.
00:44
And that's an average.
00:45
And so that varies depending on some of the elements will have additional neutrons that don't affect the charge.
00:59
And then how frequently that occurs affects the mass.
01:02
And so it's just an average mass.
01:03
And so you can see that those three things, the atomic number symbol of mass are all there.
01:08
Now, what was really neat is the way it's organized.
01:11
And so in each column going up and down, and typically denoted with these roman numerals across the top, these are all called groups.
01:27
So we have groups as are columns.
01:31
And each group have the same number of valence electrons.
01:47
I'll write that out there the same number of valence electrons.
01:56
As you can see that, say, helium here, which just has the one proton, so neutral one will have one electron means that its valence electron is one...