00:02
Hi there.
00:03
In this question, we are asked to sketch the lewis dot symbol for three different elements.
00:09
Let's talk for a moment about a lewis dot symbol.
00:11
When we are writing a lewis dot symbol, the element symbol, and we write the element symbol, that represents the nucleus of the atom and the core electrons, all of those electrons that are not in the highest energy level.
00:40
All right, and then we use dots to represent valance electrons, those electrons that are in the highest energy level.
00:56
So we need to know the number of valence electrons that each of these elements have.
01:01
We see that we have ribidium, we have silicon, and we have iodine.
01:10
So all of these are main group elements, which is great, because the group number of each main group element tells you the number of valence electrons.
01:20
So all of these elements in group 1a have one valence electron.
01:24
In 2a, they have 2, 3a3, 4, 5, 6, 7.
01:31
And except for helium, because it only has two electrons to fill its shell, all of the other noble gases have 8.
01:39
Okay, well, now we're ready to go ahead and draw our structures, our list dot symbols.
01:45
So letter a was rubidium.
01:50
Rubidium's in group 1a, so it just needs one dot.
01:55
And you can put that one dot on any of the four sides...
