00:01
We are asked to calculate the concentration of ions present in four different substances.
00:06
First, 0 .100 moles of calcium nitrate.
00:21
0 .10 moles in 100 mils of solution.
00:27
It doesn't make any difference.
00:36
For this one, the only thing that's going to make any difference is the 0 .10 moles.
00:44
It doesn't matter.
00:45
Or a concentration, i guess it does.
00:51
My bad.
00:52
0 .10 moles of calcium nitrate per 0 .1010 liters.
01:10
Next, we know that there are three moles of ions and one mole of calcium nitrate.
01:27
I'm getting my calculator out, which i should have done already, but i did.
01:31
Point one divided by point one, enter, times three, is.
01:37
3 .00 moles of ions.
01:47
And i want to make a note that each the calcium has three ions per mole.
01:57
Second, 2 .5 moles of sodium sulfate, which has 3 moles of ions per mole of salt in 1 .25 liters of solution.
02:34
2 .5 moles in a2 .8.
02:47
S .04 per 1 .25 liters times three moles of ions per mole of salt.
03:10
2 .5 divided by 1 .25, enter times 3, is 6 .0, and this should be molality, or molarity, molar, and that's my ions concentration.
03:46
Using a different pen, i haven't got used to it yet.
04:07
We'll go to the next page for c &d.
04:14
5 .00 grams of ammonium chloride in 500 .0 milliliters of solution.
04:30
And this has two moles of ions per mole of salt.
04:45
Let me get over to my molar mass tab if i can find it.
04:52
I usually just keep a molar mass tab open so i can look them up quick.
05:02
Nh4cl.
05:02
And that is 53 .49 grams per mole.
05:19
I'm going to try a little lighter thing here and see how it works on this pen...