00:01
Here we have the unit cells for cesium chloride and barium chloride.
00:06
What we want to do is look at these unit cells and determine what the net number of first ions in each of these cells are and how that corresponds and reflects on the formula for each of these compounds.
00:20
So first, if we take a look at cesium chloride, all we're going to be doing is really just counting the species as they contribute to this unit cell.
00:32
So if we look at cesium chloride, cesium is shown in purple.
00:37
There's one whole cesium inside of this cell.
00:40
It's located smack dab in the middle.
00:43
If you want to look at it this way, it's sort of in a body -centered configuration.
00:47
Now if we look at the chlorides, we have eight chlorides on each of the corners.
00:52
But because they're on the corners, it means that only one -eighth of each of these chloride ions is actually going to be located inside the unit cell, which means that there's a total of one chloride per unit cell.
01:01
Because the ratio between the two is one to one, that reflects the fact that the chemical formula for this compound is just cesium chloride, each in a one -to -one ratio.
01:11
Now if we turn our attention to barium chloride, it's a little bit more complicated, but still very much the same...