00:01
The groups within a periodic table are very important because it's the groups that contain elements with similar chemical properties.
00:08
So all of the groups are identified two different ways based upon the system.
00:14
One system, the international system, is suggested that we identify each group with a number, starting with one, going to 18, left to right, on the periodic table.
00:27
The other system is to identify the elements on the far left with a roman numeral and a letter a, and on the far right with a roman numeral and a letter a, all the way up to roman numeral 8a.
00:44
Then in the middle, we'll use a roman numeral and letter b.
00:49
This is sometimes referred to as the american system.
00:52
We'll start, though, with 3b, and then 4b, 5b, and we'll end up with one group that is all 8b, actually three groups that are 8b, and then we have our 1b and our 2b.
01:12
So, group 1a is 1.
01:18
Group 3a is 13.
01:21
Group 4a.
01:24
I'm sorry, group 5a is 15.
01:27
Group 7a is 17...