00:01
All right, we're talking about valine, this amino acid with an r group with two branched methyl groups like this.
00:08
We're going to talk about it at ph of 1, which is really, really acidic.
00:14
Over here on the left, and then we're going to talk about its structure at ph of 12, which is really, really basic.
00:19
And we're going to remember the relationship between pca and ph to answer this question.
00:25
So, valiant has a pkk, experimentally derived.
00:30
It's approximately 2 .5.
00:31
So over here on the left, ph is below pca.
00:38
So when that happens, our groups are going to be protonated.
00:43
And that means a carboxal group right here is going to retain its hydrogen, this one right here.
00:50
And then our amino group is going to have an extra hydrogen right here...