WEBVTT 00:00:00.000 --> 00:00:02.680 Let's say I have some weak acid. 00:00:02.700 --> 00:00:04.660 I'll call it HA. 00:00:04.680 --> 00:00:07.830 A is a place holder for 00:00:07.860 --> 00:00:12.800 really a whole set of elements that I could put there. 00:00:12.810 --> 00:00:15.320 It could be fluorine, it could be an ammonia molecule. 00:00:15.330 --> 00:00:16.880 If you add H it becomes ammonium. 00:00:16.890 --> 00:00:20.070 So this isn't any particular element I'm talking about. 00:00:20.080 --> 00:00:23.700 This is just kind of a general way of writing an acid. 00:00:23.720 --> 00:00:31.320 And let's say it's in equilibrium with, of course, 00:00:31.340 --> 00:00:34.480 and you've seen this multiple times, a proton. 00:00:34.500 --> 00:00:37.850 And all of this is in an aqueous solution. 00:00:37.870 --> 00:00:42.060 Between this proton jumping off of this 00:00:42.070 --> 00:00:43.610 and its conjugate base. 00:00:45.080 --> 00:00:48.290 And we also could have written a base equilibrium, 00:00:48.310 --> 00:00:50.750 where we say the conjugate base could disassociate, 00:00:50.800 --> 00:00:54.960 or it could essentially grab a hydrogen from the water 00:00:54.970 --> 00:00:56.230 and create OH. 00:00:56.250 --> 00:00:57.670 And we've done that multiple times. 00:00:57.700 --> 00:00:59.590 But that's not the point of this video. 00:00:59.610 --> 00:01:01.700 So let's just think a little bit about 00:01:01.730 --> 00:01:04.540 what would happen to this equilibrium 00:01:04.570 --> 00:01:06.620 if we were to stress it in some way. 00:01:06.640 --> 00:01:08.090 And you can already imagine 00:01:08.120 --> 00:01:11.450 that I'm about to touch on Le Chatelier's Principal, 00:01:11.470 --> 00:01:12.740 which essentially just says, look, 00:01:12.750 --> 00:01:14.320 if you stress an equilibrium in any way, 00:01:14.340 --> 00:01:17.260 the equilibrium moves in such a way 00:01:17.300 --> 00:01:18.650 to relieve that stress. 00:01:18.670 --> 00:01:22.110 So let's say that the stress that I apply to the system 00:01:27.280 --> 00:01:30.230 --Let me do a different color. 00:01:30.240 --> 00:01:33.410 I'm going to add some strong base. 00:01:33.430 --> 00:01:35.080 That's too dark. 00:01:35.100 --> 00:01:39.640 I'm going to add some NaOH. 00:01:39.660 --> 00:01:41.490 And we know this is a strong base 00:01:41.510 --> 00:01:43.110 when you put it in a aqueous solultion, 00:01:43.140 --> 00:01:46.100 the sodium part just kind of disassociates, 00:01:46.110 --> 00:01:47.660 but the more important thing, 00:01:47.670 --> 00:01:49.220 you have all this OH in the solution, 00:01:49.250 --> 00:01:50.890 which wants to grab hydrogens away. 00:01:50.900 --> 00:01:53.740 So when you add this OH to the solution, 00:01:53.760 --> 00:01:56.710 what's going to happen for every mole that you add, 00:01:56.740 --> 00:01:58.770 not even just mole, 00:01:58.800 --> 00:02:02.130 for every molecule you add of this into the solution, 00:02:02.150 --> 00:02:05.250 it's going to eat up a molecule of hydrogen. 00:02:05.270 --> 00:02:06.370 Right? 00:02:06.400 --> 00:02:07.450 So for example, if you had 00:02:07.470 --> 00:02:10.960 1 mole oh hydrogen molecules in your solution 00:02:10.980 --> 00:02:15.780 right when you do that, 00:02:15.800 --> 00:02:19.350 all this is going to react with all of that. 00:02:19.380 --> 00:02:22.750 And the OHs are going to react with the Hs 00:02:22.760 --> 00:02:24.800 and form water, 00:02:24.820 --> 00:02:26.470 and they'll both just kind of 00:02:26.480 --> 00:02:27.570 disappear into the solution. 00:02:27.580 --> 00:02:29.220 They didn't disappear, they all turned into water. 00:02:29.250 --> 00:02:32.320 And so all of this hydrogen will go away. 00:02:32.340 --> 00:02:34.350 Or at least the hydrogen that was initially there. 00:02:34.370 --> 00:02:36.970 That 1 mole of hydrogens will disappear. 00:02:37.000 --> 00:02:39.470 So what should happen to this reaction? 00:02:39.480 --> 00:02:41.740 Well, know this is an equilibrium reaction. 00:02:41.750 --> 00:02:44.080 So as these hydrogen disappear, 00:02:46.940 --> 00:02:50.630 because this is an equilibrium reaction 00:02:50.660 --> 00:02:52.280 or because this is a weak base, 00:02:52.290 --> 00:02:54.370 more of this is going to be converted 00:02:54.410 --> 00:02:58.780 into these two products 00:02:58.820 --> 00:03:01.300 to kind of make up for that loss of hydrogen. 00:03:01.320 --> 00:03:03.370 And you can even play with it on the math. 00:03:03.390 --> 00:03:07.070 So this hydrogen goes down initially, 00:03:07.090 --> 00:03:10.600 and then it starts getting to equilibrium very fast. 00:03:10.610 --> 00:03:12.240 But this is going to go down. 00:03:12.260 --> 00:03:14.720 This is going to go up. 00:03:14.740 --> 00:03:17.560 And then this is going to go down less. 00:03:17.580 --> 00:03:20.090 Because sure, when you put the sodium hydroxide there, 00:03:20.110 --> 00:03:21.970 it just ate up all of the hydrogens. 00:03:21.990 --> 00:03:23.600 But then you have this 00:03:23.620 --> 00:03:24.750 -- you can kind of view as 00:03:24.770 --> 00:03:28.460 the spare hydrogen capacity here to produce hydrogens. 00:03:28.480 --> 00:03:29.750 And when these disappear, 00:03:29.780 --> 00:03:31.980 this weak base will disassociate more. 00:03:32.000 --> 00:03:34.700 The equilibrium we'll move more in this direction. 00:03:34.720 --> 00:03:38.570 So immediately, this will eat all of that. 00:03:38.590 --> 00:03:40.490 But then when the equilibrium moves in that direction, 00:03:40.510 --> 00:03:42.580 a lot of the hydrogen will be replaced. 00:03:42.600 --> 00:03:44.680 So if you think about what's happening, 00:03:44.700 --> 00:03:48.610 if I just threw this sodium hydroxide in water. 00:03:48.630 --> 00:03:54.330 So if I just did NaOH in an aqueous solution 00:03:54.350 --> 00:03:55.690 so that's just throwing it in water 00:03:55.710 --> 00:03:57.880 -- that disassociates completely 00:03:57.900 --> 00:04:05.730 into the sodium cation and hydroxide anion. 00:04:05.750 --> 00:04:09.500 So you all of a sudden immediately 00:04:09.520 --> 00:04:12.000 increase the quantity of OHs 00:04:12.010 --> 00:04:15.060 by essentially the number of moles of 00:04:15.080 --> 00:04:16.690 sodium hydroxide you're adding, 00:04:16.710 --> 00:04:20.280 and you'd immediately increase the pH, right? 00:04:20.300 --> 00:04:22.940 Remember. When you increase the amount of OH, 00:04:22.950 --> 00:04:27.780 you would decrease the pOH, right? 00:04:27.800 --> 00:04:29.920 And that's just because it's the negative log. 00:04:29.960 --> 00:04:34.280 So if you increase OH, you're decreasing pOH, 00:04:34.300 --> 00:04:36.650 and you're increasing pH. 00:04:36.680 --> 00:04:42.280 And just think OH-- you're making it more basic. 00:04:42.290 --> 00:04:46.450 And a high pH is also very basic. 00:04:46.470 --> 00:04:49.200 If you have a mole of this, you end up with a pH of 14. 00:04:49.220 --> 00:04:51.540 And if you had a strong acid, not a strong base, 00:04:51.560 --> 00:04:53.150 you would end up with a pH of 0. 00:04:53.180 --> 00:04:56.010 Hopefully you're getting a little bit familiar 00:04:56.030 --> 00:04:57.480 with that concept right now, 00:04:57.500 --> 00:04:59.470 but if it confuses you, 00:04:59.490 --> 00:05:01.200 just play around with the logs a little bit 00:05:01.200 --> 00:05:02.210 and you'll eventually get it. 00:05:02.230 --> 00:05:03.750 But just to get back to the point, 00:05:03.770 --> 00:05:06.310 if you just did this in water, 00:05:06.330 --> 00:05:08.270 you immediately get a super high pH 00:05:08.290 --> 00:05:11.120 because the OH concentration goes through the roof. 00:05:11.140 --> 00:05:12.250 But if you do it here 00:05:12.260 --> 00:05:16.080 --if you apply the sodium hydroxide to this solution, 00:05:16.100 --> 00:05:17.470 the solution that contains 00:05:17.490 --> 00:05:20.750 a weak acid and it's conjugate base, 00:05:20.770 --> 00:05:23.840 the weak acid and its conjugate base, 00:05:23.860 --> 00:05:25.220 what happens? 00:05:25.230 --> 00:05:28.290 Sure, it immediately reacts with all of this hydrogen 00:05:28.300 --> 00:05:29.440 and eats it all up. 00:05:29.470 --> 00:05:31.110 And then you have this extras supply here 00:05:31.130 --> 00:05:33.390 that just keeps providing more and more hydrogens. 00:05:33.410 --> 00:05:34.910 And it'll make up a lot of the loss. 00:05:34.920 --> 00:05:38.410 So essentially, the stress won't be as bad. 00:05:38.430 --> 00:05:42.170 And over here, you dramatically increase the pH 00:05:42.200 --> 00:05:43.990 when you just throw it on water. 00:05:44.000 --> 00:05:46.630 Here, you're going to increase the pH by a lot less. 00:05:46.640 --> 00:05:50.430 And in future videos, we'll actually do the math of 00:05:50.450 --> 00:05:52.680 how much less it's increasing the pH. 00:05:52.700 --> 00:05:54.350 But the way you could think about it is, 00:05:54.370 --> 00:05:57.000 this is kind of a shock absorber for pH. 00:05:57.020 --> 00:05:59.330 Even though you threw this strong based 00:05:59.350 --> 00:06:01.050 into this solution, 00:06:01.070 --> 00:06:02.770 it didn't increase the pH 00:06:02.790 --> 00:06:04.460 as much as you would have expected. 00:06:04.470 --> 00:06:05.710 And you can make it the other way. 00:06:05.730 --> 00:06:07.930 If I just wrote this exact same reaction 00:06:07.940 --> 00:06:09.050 as a basic reaction 00:06:09.060 --> 00:06:12.120 --and remember, this is the same thing. 00:06:12.140 --> 00:06:15.650 So if I just wrote this as, A minus 00:06:15.670 --> 00:06:17.490 --so I just wrote its conjugate base-- 00:06:17.510 --> 00:06:22.040 is in equilibrium with the conjugate base 00:06:22.060 --> 00:06:27.620 grabbing some water from the surrounding aqueous solution. 00:06:27.650 --> 00:06:29.100 Everything we're dealing with right now 00:06:29.120 --> 00:06:30.170 is an aqueous solution. 00:06:30.190 --> 00:06:32.570 And of course that water that it grabbed from 00:06:32.580 --> 00:06:33.740 is not going to be an OH. 00:06:33.750 --> 00:06:36.730 Remember, are just equivalent reactions. 00:06:36.750 --> 00:06:38.990 Here, I'm writing it as an acidic reaction. 00:06:39.010 --> 00:06:40.640 Here, I'm writing it is a basic reaction. 00:06:40.660 --> 00:06:41.700 But they're equivalent. 00:06:41.720 --> 00:06:42.750 Now. 00:06:42.770 --> 00:06:46.470 If you were to add a strong acid to the solution, 00:06:46.480 --> 00:06:47.650 what would happen? 00:06:47.670 --> 00:06:50.830 So if I were to throw hydrogen chloride into this. 00:06:50.850 --> 00:06:53.880 Well hydrogen chloride, if you just throw it 00:06:53.890 --> 00:06:56.940 into straight up water without the solution, 00:06:56.960 --> 00:06:58.480 it would completely disassociate into 00:06:58.510 --> 00:07:04.810 a bunch of hydrogens and a bunch of chlorine anions. 00:07:04.830 --> 00:07:07.190 And it would immediately make it very acidic. 00:07:07.210 --> 00:07:09.000 You would get to a very low pH. 00:07:09.020 --> 00:07:10.870 If you had a mole of this 00:07:10.890 --> 00:07:12.870 --if your concentration was 1 molar, 00:07:12.900 --> 00:07:15.050 then this will go to a pH of 0. 00:07:15.070 --> 00:07:17.790 But what happens if you add hydrochloric acid to 00:07:17.810 --> 00:07:20.680 this solution right here? 00:07:20.690 --> 00:07:22.340 This one that has this weak base 00:07:22.370 --> 00:07:24.540 and its conjugate weak acid? 00:07:24.550 --> 00:07:28.780 Well, all of these hydrogen protons that 00:07:28.800 --> 00:07:30.340 disassociate from the hydrochloric acid 00:07:30.350 --> 00:07:33.000 are all going to react with these OHs you have here. 00:07:33.020 --> 00:07:35.520 And they're just going to cancel each other out. 00:07:35.540 --> 00:07:38.000 They're just going to merge with these and turn into water 00:07:38.020 --> 00:07:39.810 and become part of the aqueous solution. 00:07:39.830 --> 00:07:43.080 So this, the OHs are going to go down initially, 00:07:43.100 --> 00:07:46.920 but then you have this reserve of weak base here. 00:07:46.940 --> 00:07:49.380 And Le Chatelier's Principal tells us. 00:07:49.390 --> 00:07:51.450 Look, if we have a stressor 00:07:51.460 --> 00:07:55.270 that is decreasing our overall concentration of OH, 00:07:55.290 --> 00:07:57.290 then the reaction is going to 00:07:57.300 --> 00:08:00.350 move in the direction that relieves that stress. 00:08:00.360 --> 00:08:02.700 So the reaction is going to go in that direction. 00:08:02.720 --> 00:08:05.220 So you're going to have more of our weak base 00:08:05.240 --> 00:08:07.720 turning into a weak acid and producing more OH. 00:08:07.750 --> 00:08:12.560 So the pH won't go down as much as you would expect 00:08:12.570 --> 00:08:13.990 if you just threw this in water. 00:08:14.010 --> 00:08:15.750 This is going to lower the pH, 00:08:15.760 --> 00:08:18.290 but then you have more OH that could be produced as 00:08:18.300 --> 00:08:21.020 this guy grabs more and more hydrogens from the water. 00:08:21.040 --> 00:08:23.480 So the way to think about it is it's kind of like 00:08:23.500 --> 00:08:26.650 a cushion or a spring in terms of what 00:08:26.670 --> 00:08:30.960 a strong acid or base could do to the solution. 00:08:30.970 --> 00:08:33.520 And that's why it's called a buffer. 00:08:38.650 --> 00:08:41.660 Because it provides a cushion on acidity. 00:08:41.680 --> 00:08:44.090 If you add a strong base to water, 00:08:44.110 --> 00:08:46.820 you immediately increase its pH. 00:08:46.840 --> 00:08:49.050 Or you decrease its acidity dramatically. 00:08:49.070 --> 00:08:51.270 But if you add a strong base to a buffer, 00:08:51.290 --> 00:08:53.800 because of Le Chatelier's Principal, 00:08:53.810 --> 00:08:56.420 essentially, you're not going to affect the pH as much. 00:08:56.440 --> 00:08:57.470 Same thing. 00:08:57.490 --> 00:08:59.720 If you add and acid to that same buffer, 00:08:59.730 --> 00:09:01.810 it's not going to affect the pH 00:09:01.820 --> 00:09:03.510 as much as you would have expected 00:09:03.530 --> 00:09:05.220 if you had thrown that acid in water 00:09:05.230 --> 00:09:07.990 because the equilibrium reaction can always 00:09:08.000 --> 00:09:11.510 kind of refill the amount of OH that you lost 00:09:11.530 --> 00:09:13.000 if you're adding acid, 00:09:13.020 --> 00:09:16.010 or it can refill the amount of hydrogen you lost 00:09:16.030 --> 00:09:17.860 if you're adding a base. 00:09:17.880 --> 00:09:20.140 And that's why it's called buffer. It provides a cushion. 00:09:20.150 --> 00:09:23.320 So it give some stability to the solution's pH. 00:09:23.340 --> 00:09:30.630 The definition of a buffer is 00:09:30.650 --> 00:09:34.450 just a solution of a weak acid in equilibrium 00:09:34.470 --> 00:09:36.370 with its conjugate weak base. 00:09:36.400 --> 00:09:38.450 That's what a buffer is, and it's called a buffer 00:09:38.480 --> 00:09:40.920 because it provides you this kind of cushion of pH. 00:09:40.960 --> 00:09:43.300 It's kind of a stress absorber, 00:09:43.320 --> 00:09:46.560 or a shock absorber for the acidity of a solution. 00:09:46.590 --> 00:09:48.540 Now, with that said, 00:09:48.570 --> 00:09:51.390 let's explore a little bit the math of a buffer, 00:09:51.400 --> 00:09:54.390 which is really just the math of a weak acid. 00:09:54.410 --> 00:09:57.780 So if we rewrite the equation again, 00:09:57.800 --> 00:10:01.780 so HA is in equilibrium. 00:10:01.800 --> 00:10:04.790 Everything's in an aqueous solution. 00:10:04.810 --> 00:10:10.160 With hydrogen and its conjugate base. 00:10:10.180 --> 00:10:15.020 We know that there's an equilibrium constant for this. 00:10:15.040 --> 00:10:17.420 We've done many videos on that. 00:10:17.440 --> 00:10:20.060 The equilibrium constant here is equal to 00:10:20.080 --> 00:10:23.650 the concentration of our hydrogen proton 00:10:23.660 --> 00:10:26.730 times the concentration of our conjugate base. 00:10:26.750 --> 00:10:29.890 When I say concentration, I'm talking molarity. 00:10:29.900 --> 00:10:32.880 Moles per liter divided by 00:10:32.900 --> 00:10:34.530 the concentration of our weak acid. 00:10:34.550 --> 00:10:36.510 Now. 00:10:36.530 --> 00:10:43.950 Let's solve for hydrogen concentration. 00:10:43.970 --> 00:10:45.890 Because what I want to do is 00:10:45.920 --> 00:10:47.040 I want to figure out a formula, 00:10:47.060 --> 00:10:49.840 and we'll call it the Hendersen-Hasselbalch Formula, 00:10:49.860 --> 00:10:52.190 which a lot of books want you to memorize, 00:10:52.200 --> 00:10:53.630 which I don't think you should. 00:10:53.640 --> 00:10:54.770 I think you should always just be able to 00:10:54.790 --> 00:10:57.710 go from this kind of basic assumption and get to it. 00:10:57.720 --> 00:10:59.410 But let's solve for the hydrogen 00:10:59.420 --> 00:11:00.960 so we can figure out a relationship 00:11:00.980 --> 00:11:03.580 between pH and all the other stuff that's in this formula. 00:11:03.590 --> 00:11:06.270 So, if we want to solve for hydrogen, 00:11:06.290 --> 00:11:07.540 we can multiply both sides 00:11:07.560 --> 00:11:10.390 by the reciprocal of this right here. 00:11:10.400 --> 00:11:14.050 And you get hydrogen concentration. 00:11:14.060 --> 00:11:19.010 Ka times 00:11:19.020 --> 00:11:21.470 --I'm multiplying both sides times a reciprocal of that. 00:11:21.480 --> 00:11:24.990 So times the concentration of our weak acid 00:11:25.010 --> 00:11:28.110 divided by the concentration of our weak base 00:11:28.130 --> 00:11:34.420 is equal to our concentration of our hydrogen. 00:11:34.430 --> 00:11:36.270 Fair enough. 00:11:36.290 --> 00:11:37.310 Now. 00:11:37.320 --> 00:11:39.270 Let's take the negative log of both sides. 00:11:39.280 --> 00:11:47.840 So the negative log of all of that stuff, 00:11:47.850 --> 00:11:51.860 of your acidic equilibrium constant, 00:11:51.880 --> 00:12:03.030 times HA, our weak acid divided by our weak base, 00:12:03.050 --> 00:12:07.040 is equal to the negative log of 00:12:07.070 --> 00:12:08.290 our hydrogen concentration. 00:12:08.300 --> 00:12:10.030 Which is just our pH, right? 00:12:10.050 --> 00:12:13.140 Negative log of hydrogen concentration is 00:12:13.160 --> 00:12:15.460 --that's the definition of pH. 00:12:15.480 --> 00:12:18.310 I'll write the p and the H in different colors. 00:12:18.350 --> 00:12:20.060 You know a p just means negative log. 00:12:20.070 --> 00:12:23.350 Minus log. That's all. Base 10. 00:12:23.390 --> 00:12:25.730 Let's see if we can simplify this any more. 00:12:25.760 --> 00:12:29.610 So our logarithmic properties. 00:12:29.640 --> 00:12:34.000 We know that when you take the log of something 00:12:34.020 --> 00:12:35.070 and you multiply it, 00:12:35.090 --> 00:12:36.820 that's the same thing as taking the log of this 00:12:36.850 --> 00:12:38.130 plus the log of that. 00:12:38.150 --> 00:12:46.350 So this can to be simplified to minus log of our Ka minus 00:12:46.380 --> 00:12:57.210 the log of our weak acid concentration divided by 00:12:57.220 --> 00:12:58.870 its conjugate base concentration. 00:12:58.890 --> 00:13:03.270 Is equal to the pH. 00:13:03.280 --> 00:13:08.230 Now, this is just the pKa of our weak acid, 00:13:08.250 --> 00:13:09.940 which is just the negative log of 00:13:09.950 --> 00:13:13.160 its equilibrium constant. 00:13:13.170 --> 00:13:14.490 So this is just the pKa. 00:13:14.520 --> 00:13:18.590 And the minus log of HA over A. 00:13:18.600 --> 00:13:21.690 What we can do is we could make this a plus, 00:13:21.710 --> 00:13:24.350 and just take this to the minus 1 power. Right? 00:13:24.370 --> 00:13:25.930 That's just another logarithm property, 00:13:25.950 --> 00:13:27.730 and you can review the logarithm videos 00:13:27.760 --> 00:13:28.780 if that confused you. 00:13:28.810 --> 00:13:31.310 And this to the minus 1 power just means invert this. 00:13:31.330 --> 00:13:32.340 So we could say, 00:13:32.360 --> 00:13:37.390 plus the logarithm of our conjugate base concentration 00:13:37.400 --> 00:13:40.230 divided by the weak acid concentration 00:13:40.240 --> 00:13:43.090 is equal to the pH. 00:13:43.110 --> 00:13:44.540 And this right here, 00:13:44.560 --> 00:13:47.110 this is called the Hendersen-Hasselbalch Equation. 00:13:47.120 --> 00:13:51.680 And I really encourage you not to memorize it. 00:13:51.700 --> 00:13:54.270 Because if you do attempt to memorize it, 00:13:54.280 --> 00:13:56.980 within a few hours, you're going to forget 00:13:57.000 --> 00:13:58.470 whether this was a plus over here. 00:13:58.480 --> 00:13:59.880 You're going to forget this, 00:13:59.900 --> 00:14:01.850 and you're going to forget whether you 00:14:01.870 --> 00:14:03.360 put the A minus or the HA 00:14:03.390 --> 00:14:04.750 on the numerator or the demoninator, 00:14:04.770 --> 00:14:06.040 and if you forget that, it's fatal. 00:14:06.070 --> 00:14:07.800 The better thing is to just start 00:14:07.820 --> 00:14:10.250 from your base assumptions. And trust me. 00:14:10.270 --> 00:14:11.610 It took me a couple minutes to do it, 00:14:11.630 --> 00:14:13.240 but if you just do it really fast on paper, 00:14:13.270 --> 00:14:14.940 you don't have to talk it through the way I did 00:14:14.970 --> 00:14:18.060 --it'll take in no time at all to come to this equation. 00:14:18.070 --> 00:14:19.410 It's much better than memorizing it, 00:14:19.430 --> 00:14:22.350 and you won't forget it when you're 30 years old. 00:14:22.370 --> 00:14:24.750 But what's useful about this? 00:14:24.760 --> 00:14:28.830 Well, it immediately relates pH to our pKa, 00:14:28.840 --> 00:14:31.370 and this is a constant, right, for an equilibrium? 00:14:31.400 --> 00:14:35.120 Plus the log of the ratios between the acid 00:14:35.140 --> 00:14:37.050 and the conjugate base. 00:14:37.080 --> 00:14:40.410 So the more conjugate base I have, 00:14:40.430 --> 00:14:42.590 and the less acid I have, 00:14:42.610 --> 00:14:45.470 the more my pH is going to increase. Right? 00:14:45.490 --> 00:14:47.770 If this goes up and this is going down, 00:14:47.790 --> 00:14:49.100 my pH is going to increase. Which makes sense 00:14:49.110 --> 00:14:51.270 because I have more base in the solution. 00:14:51.280 --> 00:14:52.870 And if I have the inverse of that, 00:14:52.900 --> 00:14:54.700 might be just going...