00:01
All right.
00:02
So in this question, we're given 0 .3 moles per liter of some unknown base.
00:08
We know that the ph that results from it is 10 .66.
00:13
And what we've got to find is the kb value or the ionization constants.
00:21
Okay, so an important thing when finding the ionization constant is the hydroxide concentration.
00:29
So let's use this ph to find the hydroxide concentration.
00:35
So the first thing to remember is ph plus p .o .h equals 14, which means the p .o .h would be 14 minus 10 .66, leaving you with a value of 3 .34.
00:48
So let's take that and find the hydroxide concentration by doing the antilog of negative 3 .34, which is 10 to the negative 3 .34.
01:00
Which will give you a value of 4 .6 times 10 to the negative 4.
01:06
All right.
01:07
Now, that should help us to get this value to the cyanization constant.
01:17
Now, let's make sure we know what we need.
01:21
We need the hb plus.
01:23
That's like the conjugate acid concentration times the hydroxide concentration, which we just found, divided by the base concentration, not exactly the 0 .3 we started with, but whatever's left at equilibrium.
01:41
So we know the hydroxide concentration is 4 .6 % of the negative 4.
01:46
We just found that.
01:50
That's also going to be the same as the conjugate acid concentration or the cadion...