00:01
Hello, everyone.
00:01
This is ricky, and today we're working on problem number 99.
00:05
So we have to calculate the ph at which magnesium sulf, sulfur, sulfide, will begin to precipitate when it is in a solution that is 0 .125 molar magnesium nitrate and when it itself has a concentration of 0 .1 .molar molar.
00:30
And so we know the concentration of manganese nitrate because, or of manganese ion, because manganese nitrate completely dissociates in solution.
00:45
All right.
00:51
I've written down the ksp expressions for the precipitation of manganese sulfide and the ka expression for h2s reacting with water.
01:12
And now what we're going to be doing is solving for the sulfide ion concentration.
01:25
So let's rewrite our expression and plus my apologies.
01:34
It would be sulfur or sulfide.
01:46
I don't know, just one one there.
01:47
That was a little wonky...