00:01
So we want to know about the ph at the equivalence point in the titration of a weak acid.
00:08
Let's say, for example, hcn.
00:11
And we're going to titrate that with a strong base like k -o -h.
00:17
And let's say that we initially have one mole of the h -zn.
00:22
Then it's going to require one mole of the k -o -h to consume it because it's, it's understood that there's a one here and a one here, this would be the balanced equation.
00:36
And we would produce kcn.
00:43
Let's write that as a net ionic k -plus plus cn minus plus h -2o.
00:54
And the reason i wanted to separate those is you'll have a mole of k -plus, but potassium ion does not have any acid -based activity.
01:14
So let's do this in terms of our initial concentration and our final concentration.
01:26
And so initially we had none of the product.
01:29
Of course, the water is there in high concentration and doesn't change its concentration...