The Secret Science Behind this Medication is WILD

[00:00:00]I got my gargoyles on, that means this is serious.

[00:00:02]>> Okay, this is not very practical right now.

[00:00:05]>> This is Pepto-Bismol and it's been the source of a lot of interest lately. This is a medication used for heartburn and a lot of people love it and I know exactly why. It's a good medication. But the science behind this is very interesting and I think pretty much everybody should be able to understand this. The way this works is a fundamental principle not only in chemistry, but in life itself.

[00:00:27]So, I want to show you guys exactly how this works. I have lots of different experiences here to drive this point home. I'm Grant Harding. I'm a licensed pharmacist in four states and chemistry is cool. So, we need to start from the beginning. Plain old water. Let me turn this camera around and I'm going to show you all sorts of different principles in chemistry or actually just one principle really. But it's going to apply to like several different things and then finally we'll culminate with the Pepto-Bismol and and you'll be able to understand how this actually works. Uh to be able to fully grasp Pepto-Bismol, we have to start from the beginning.

[00:00:59]This is just plain water. And what we like to do a lot of the times in pharmacy and chemistry is know what the pH is. So, these are little pH strips.

[00:01:09]You just dip them in here and then there's a little bit of a change in the color of the strip and then you can kind of match it to these numbers here and it'll tell you what the pH is.

[00:01:19]So, when I dip this in, water is pretty neutral. I mean, maybe it's a little bit acidic.

[00:01:24]We're looking at Actually, that looks a little basic. Whatever, it's around seven, okay?

[00:01:28]Now, pH technically speaking is the concentration of hydrogen ions in a solution.

[00:01:35]And why the heck is that relevant? Well, it's hyper relevant actually. Right now, we just have water in here, which is H2O. And to some extent, water kind of pulls hydrogen off of other uh water molecules and it kind of like passes this hydrogen back and forth. It's not really that significant and it doesn't fully pull it off the water, but just know that whenever you look at a solution, even just water, it's not just static.

[00:02:03]There's a lot going on. And the pH scale is kind of inverse. So, the lower the pH, the higher the concentration of hydrogen ions, and the more acidic something is. So, if we want to make this more acidic, we use my favorite chemical ever, lysergic acid diethylamide.

[00:02:21]Okay, it looks like there was a mistake at the warehouse, and I only got hydrochloric acid. That's fine.

[00:02:26]That will still work. So, hydrochloric acid is a combination of hydrogen and chlorine.

[00:02:32]And the cool part about this is it's a strong acid, meaning whenever you put this in water, the the water molecules are going to pull that hydrogen and that chlorine apart completely.

[00:02:46]They will be basically separated once I put this into the solution. Look, I'm only going to put a little bit in there.

[00:02:53]That's hardly anything at all.

[00:02:56]Now, let's just give this a little mixer doodle do.

[00:02:59]So, yes, we put hydrogen chloride in there, but the only thing we care about is the hydrogen. The chlorine just kind of sits by itself, like Steven Glansberg. Nobody really cares about it, at least at this stage.

[00:03:12]So, look, you can see the pH went down quite a bit. I mean, now it's at like four. So, we went from seven to four. That's a pretty significant change in pH, right? Because we increased the hydrogen ion concentration. So, then, if we want to raise the pH, we have to pull some of those hydrogen ions out. And for that, I'm going to use sodium hydroxide. And sodium hydroxide is a sodium atom with oxygen and hydrogen.

[00:03:40]Now, whenever this pulls apart in solution, which is what it will do here whenever I drop some little drippy drops in, we'll have sodium and then hydroxide swimming around freely, independently, just kind of hanging out.

[00:03:57]And the sodium will bind with the chlorine, and we don't care. But, hydroxide is an oxygen and a hydrogen.

[00:04:03]So, we're very close to making water.

[00:04:06]And that's what it does.

[00:04:08]The hydrogen and the oxygen bind to all those hydrogen ions that were in there from the hydrochloric acid, and it just makes water.

[00:04:16]And it pulls those hydrogen ions out of solution. So, let's just put a little bit in here.

[00:04:22]Maybe just a little tad more.

[00:04:26]Stir that bad boy up.

[00:04:29]All right. Is anyone super astute based on just looking at me putting that sodium hydroxide in there? What do you think the pH is going to be? I'm going to say I tried to make it a little bit more than seven. I tried to make it eight, but I think my number or my estimates may be off here. I think it's probably around seven.

[00:04:46]Nope. I didn't put my enough in. Okay, so it's still pretty acidic. Let's put a little bit more sodium hydroxide in.

[00:04:52]Okay, now it's going to be quite basic.

[00:04:55]Pulling all of those hydrogen ions out and making water.

[00:05:00]So, here we go.

[00:05:02]And yeah, it did pull them all out. So, it's around seven now. So, it took way more sodium hydroxide than what I imagined, but you get the point. It only took a couple drops of the hydrochloric acid to get down, and it took quite a bit of sodium hydroxide to get it back up to seven.

[00:05:19]Okay, let's take this step further, and let's use cleaning vinegar, which I didn't even know existed. Why would anybody What's the difference between cleaning vinegar and like eating vinegar? Cuz I didn't know that there was cleaning vinegar. I just went to the Dollar Tree, and this is all they had. So, cleaning vinegar is acidic, but it's not nearly as acidic as hydrochloric acid. Very important point.

[00:05:42]Meaning, whenever I put this in solution, we'll get some hydrogen ions.

[00:05:47]Uh they're being dispersed. The uh acid in here is called acetic acid, BT dubs.

[00:05:53]Oh, I don't think this is going to work.

[00:05:54]This does not smell like regular vinegar. Well, let's see.

[00:05:59]It mean it very clearly is mixed with some sort of soap, but I think the point will still be appropriate. Acetic acid, the active chemical or the important chemical in vinegar, whenever that gets dispersed in the solution, it pulls hydrogen off, but not completely. It's kind of like they don't really want to let go of the hydrogen ion, whereas in hydrochloric acid, it's like, "Dude, take it. Like, get me away from this thing."

[00:06:23]So, it's only a little bit acidic.

[00:06:27]We're looking at I don't know, four, five-ish, somewhere around there.

[00:06:32]Now, if I put baking soda in here, which the active chemical is sodium bicarbonate, again, this is similar to sodium hydroxide. It's It's basic. So, it'll cause this reaction to occur, and you'll see some gas release.

[00:06:51]Yeah, that was very boring.

[00:06:53]Cleaning vinegar, not fun.

[00:06:55]So, apparently, cleaning vinegar is different from eating vinegar.

[00:07:00]But, you can see the reaction has occurred, and there is some gas being released, and it's kind of foamy in there.

[00:07:06]Okay, just for fun, let's put some hydrochloric acid in water, so you can see like what the reaction really should look like.

[00:07:12]Now, when I put the baking soda in, it's going to be much more violent, cuz this is a stronger acid, right?

[00:07:17]See?

[00:07:19]I mean, you can see the bubbling. So, it's releasing carbon dioxide. The sodium bicarbonate pulls the hydrogen out of solution, and then it it has like an intermediate uh chemical, and then it just kind of breaks apart into water and carbon dioxide. So, that's what happens there. Effectively neutralizing the acid.

[00:07:40]And if we go back to our vinaigrette, now the pH of this should be much more basic, and indeed it is. See, we're looking in the greens now.

[00:07:50]It's like eight, nine, cuz I put so much uh sodium bicarbonate in there. Okay, at this point you get the point. Acids, when added to a solution, they get away from their little hydrogen ion, and their hydrogen ion is swimming around here like it's a lost puppy.

[00:08:04]And the more of that hydrogen ion that we have, you know, the higher or the lower the pH, which is, you know, the higher the concentration of the hydrogen ions. So, what's that have to do with Pepto-Bismol? Well, when you look at this box, it has citric acid and sodium bicarbonate. Now, the sodium bicarbonate is just baking soda.

[00:08:26]And the citric acid is a weak acid, kind of like uh the acetic acid from vinegar, although the one I got here today wasn't the best example of that. And this lowers stomach acid. So, if you have acid reflux or whatever, uh that can be quite uncomfortable, especially when it creeps up, you know, into your um esophagus and whatnot. So, taking this will lower stomach acid, but why the heck is there citric acid here? Like, what what is the point of that? Well, I'm going to explain that to you, and it's one of the fundamental parts of chemistry. So, in here we have citric acid, which I will denote like this, H cit.

[00:09:06]Citric acid, okay?

[00:09:08]Now, whenever that dissolves in water, the the hydrogen pulls apart, but not really a whole lot.

[00:09:16]It kind of like m- it's mostly still citric acid, but a little bit of it comes out into hydrogen, and then citric acid without the hydrogen is called citrate, which I'll call CIT minus. So, basically we have like 10 citric acids and like two um probably like three citrates and like I don't know, maybe two hydrogens. Uh all I'm saying is whenever this gets dissolved in water, it's mostly citric acid still. But that's not all that's in this package. Remember sodium bicarbonate, which is a base. It will pull these hydrogen ions out. And when it does that, it shifts this equation.

[00:10:06]Now we have 10 citric acids. Well, if you pull, let's say two of these hydrogen ions out, it needs to be replaced.

[00:10:15]So, let's say it pulled two of these out.

[00:10:18]They that that still needs to have two hydrogen ions here. So, this goes down to eight.

[00:10:24]And then maybe this goes up to five. It It creates an equilibrium. So, in other words, there's a ton of citric acid in here, relatively speaking. So, what happens whenever I dump this into water is you have citric acid and let's say we have a ton of this.

[00:10:40]Let's say it's like 100.

[00:10:44]And then it combines uh with the sodium bicarbonate.

[00:10:48]HCO3 is bicarbonate. This is sodium bicarbonate.

[00:10:52]And what you get is sodium citrate CO2, which is carbon dioxide, and just water, H2O.

[00:11:01]Now, we don't care about any of this.

[00:11:04]Uh I hate it when a chemistry nerds get all like excited about balancing the equation. Nobody cares. We don't even care about the sodium.

[00:11:10]We don't We don't care.

[00:11:12]All we care about is that there's a lot of sodium cit- or uh citric acid after this reaction takes place, let's say it's down to like 80.

[00:11:22]I don't know. And then it creates this equilibrium with the hydrogen ion, obviously. And then the citrate sodium citrate from before, the sodium gets pulled apart and then all the citrate comes down here.

[00:11:37]And after this reaction occurs, all the sodium bicarbonate gets used up and all you're left with with is citric acid and citrate. Basically, it's all the only parts we care about.

[00:11:50]And I don't know, let's say it's about equal. Let's say somehow you end up with 80 citrate. And I don't know, let's call this like 20 of the hydrogen ion. So now, after this reaction occurs, you have a lot of both these.

[00:12:08]And as you pull hydrogen out, it's going to shift to replace that hydrogen.

[00:12:15]This is kind of like gas, I guess. This is the fuel for this machine, this chemical machine.

[00:12:21]And as you pull hydrogen out, this will shift and it'll replace the hydrogen and then of course you'll get more citrate.

[00:12:29]And as you put hydrogen in to the solution, the exact same thing or the exact opposite happens before.

[00:12:35]The hydrogen will bind with the citrate and it'll make citric acid and then the numbers of citrate will go down. Let's call it like 78.

[00:12:44]And this will go to like 82 or something like that.

[00:12:47]So it's like this balance of these ions, these hydrogen ions. And this will occur for as long as you have appropriate amounts of both citric acid and citrate.

[00:13:00]Once those run out, then this whole function dies. So previously, when we were screwing around with the hydrochloric acid and the sodium hydroxide, if you would add hydrochloric acid, you would add hydrogen to a solution. The hydrogen ion concentration would just increase because you're putting more in the solution. But down in here, if you add hydrogen, it's not going to change. It's going to get chewed up by the citrate and then it's going to get converted into citric acid.

[00:13:28]So, the the concentration of the hydrogen, whenever you're using Peecat, it stays the same, relatively. I mean, it's not exactly, but it's resistant to any pH change. So, let's take a look at this.

[00:13:42]These little packets, you know, this is our um citric acid and sodium bicarbonate.

[00:13:48]And I put this in here, we'll see a little fizz, it's going to make the carbon dioxide.

[00:13:53]People love that. They love the the fizziness of this.

[00:14:01]Woohoo!

[00:14:03]Don't mind me, I'm just mixing up my citric acid buffer solution.

[00:14:10]All right. Now, here's where things get interesting. Let's take this pH, it should be somewhere between three and six.

[00:14:20]Oh, six. It's like six. All right, perfect. Remember earlier whenever I added just a little bit of hydrochloric acid to that water and the pH went down a couple points? Watch what happens now.

[00:14:38]So, we introduced hydrogen ions to the solution. It was at a pH of about six.

[00:14:44]But because we have both citric acid and citrate, it's just going to gobble up that hydrogen excess and it's going to stay at equilibrium.

[00:14:55]So, the pH probably went down a little bit, but it wasn't going to be nearly as significant as what it was without this uh citric acid and citrate buffered solution. All right, I believe it went down to like four whenever we were just using water.

[00:15:10]Look at that.

[00:15:12]It's still at six. It didn't change at all. Okay, let's see if we can get it to move any. Um I mean, we will eventually.

[00:15:20]If you dump enough in here, it'll, you know, get rid of the uh important parts.

[00:15:24]Here, let's just get crazy.

[00:15:28]That was considerably more than what we've ever used before in any stage of this experiment.

[00:15:37]Yeah, we're down we're down to around five now. Okay, so it's started to come down. Now, let's take it the other way.

[00:15:43]Let's see here. Let's dump a considerable amount cuz remember it took a good bit of the sodium hydroxide earlier to move the pH a little bit. So, let's consider that now that we have a buffered solution.

[00:15:56]Put just a tad more in. Okay, so that was a good bit.

[00:16:00]We were at five-ish if I recall correctly.

[00:16:05]Look at that.

[00:16:08]You can't change it.

[00:16:10]I mean, you can. It's still at five.

[00:16:12]But, it's very resistant to any change in pH in either direction.

[00:16:17]So, as we've seen here today, Pepto-Bismol is more than just an antacid, really. It's a buffer. It resists change in either direction. Now, there's a couple points about this that you may be wondering, at least you should be.

[00:16:29]What's the point of doing that in the stomach? I don't think there is. I did the math, and my calculations show that if you put that this, you know, Pepto-Bismol water solution in your stomach, your stomach is going to absolutely destroy the buffer. There's enough volume and enough acidity in your stomach that the fact that this is a buffer shouldn't matter.

[00:16:51]That's how I'm seeing this. But, the result is still what you intended. The stomach acid is going to be reduced to some extent. Remember, we put this in the water, and it was a pH of six.

[00:17:00]Uh your stomach is a pH of like two. So, six is considerably higher than two.

[00:17:05]Whenever you put that in there, it's going to raise it to some extent. And it's good. It works.

[00:17:11]The fact that it's a buffer just really doesn't matter. At least, that's how I'm seeing this. Now, if you would swallow like a ton, like gallons of this, then yeah, it would make a buffered solution in your stomach and that would probably be a bad idea, I would think. Couple questions I still have and I'd like to hear from you guys if you have any um thoughts on this. Why don't they just sell this the citric acid and the the citrate or sodium citrate and and citric acid? Why don't they just sell that together? Why go through the process of, you know, going through this chemical reaction in a glass and then swallowing it to make the buffer? You know, it looks cool when you dump it in the water, you know, it's a little bit of a marketing technique. And two, they actually do sell uh citric acid buffers and it is a real medicine and you can buy it, but it requires a prescription. So, you're sort of making a prescription product here with over-the-counter ingredients. Pretty nifty, pretty smart, I think. But, a lot of times buffered solutions are made from this exact reaction anyway, so I don't know. Whatever, it's just cool.

[00:18:13]But, this concept of a buffer in chemistry is not something that's just a unique quirk. It's not just a little factoid that you can talk about your friends and it's a cool party trick or something. This is crucial for life itself. Or to be more specific with mammals. But, this same process, what I showed you here, you know, when we put the pea cot in the water, we put the acid and the base in it and it didn't change, that's exactly what happens in your blood. I believe it uses carbonic acid and without that, pH changes can get wild and enzymes in your body can degrade because if there's too much hydrogen ion concentration, it can break chemicals apart and particularly ones that are crucial for life. So, I always find these little things, you know, that doesn't seem that significant, just seems like neat.

[00:19:06]But, in fact, they're actually crucial for life itself. That was a lot of fun.

[00:19:11]Stick around and make all sorts of cool little videos like this.