00:01
So we had to calculate the ph of the mixture of 35 mil sample of 0 .15 molar acetic acid with these volumes of 0 .15 molar sodium hydroxide.
00:18
So to start with, the first one, a, 0 mil of the sodium hydroxide.
00:25
So we have 35 mil of 0 .15 molar acetic acid.
00:32
So here we didn't have any sodium nitroxia.
00:35
So we only have the acetic acid.
00:38
And having only the acetic acid acid, we know the concentration already.
00:42
So we can just go ahead and calculate the ph and that'll be negative logarithm of 0 .15 and that's 0 .82.
00:49
Okay.
00:51
And b is we have 17 .5.
00:55
17 .5m .m.
01:00
Of the sodiumide oxide.
01:04
Okay.
01:05
So here it's a little bit different because now we need to know how the reaction happened.
01:10
So we have acetic acid reacting with sodium hydroxide.
01:17
We'll have a formation of the sodium acetate and water.
01:25
Right.
01:25
So the stochymetry for the reaction is one to one.
01:29
Okay.
01:30
So, um, here.
01:34
Here we have the concentration of the sodium my drugs are to be 0 .15 molar.
01:39
So we can determine the number of mole of this.
01:41
So this should be 17 .5 divided by 1000 because we are trying to make this in liters multiply by 0 .15 molar.
01:55
So that will give us a number of mole.
01:56
So this is 17 .5, 1 ,000.
02:09
So this is 0 .0026.
02:15
That is the number of moles of sodium my drugs are here.
02:22
So we have a 0 .002625 more of an a.
02:32
Then we have a 35 .0 mil of 0 .15 molar acetic acid.
02:41
So we're going to do the same thing, 35 25 divided by 1000 multiplied by 0 .15 molar, who give us the number of mol of acetic acid.
02:52
So that's going to be 35 divided by 1000 times 0 .15, and that is 0 .005 .25 more.
03:06
And we can see right from here that we have more number of more of acidic acid than the sodium my drugsyte.
03:14
So that means we're going to have excess of the acetic acid by this among 0 .00525 minus 0 .002625...