 Hey everybody, in this video we're going to talk about the pH scale before we do so let's talk about what acids and bases are. So you see at the top an acid is anything that donates hydrogen ions to a solution because the more hydrogen ions they are the lower the pH will be. A base is anything that accepts hydrogen ions and raises the pH. Now how it does so is you see here bases have a lot of hydroxide ions. They are going to bond to a hydrogen ion forming water and that's how they pull hydrogen ions out of a solution. So acids donate hydrogen ions and lower the pH bases accept hydrogen ions and raise the pH. So here we see the pH scale. It means it's very important to remember hydrogen ions are super reactive and essential but if you have too many hydrogen ions or too few hydrogen ions lots and lots of health problems would develop. That's where we'll cover acidosis conditions where the pH is too low and alkalosis conditions where the pH is too high later. Right now we're just talking about the scale. But just keep that in mind. The pH is the partial pressure or the concentration of hydrogen ions. The more hydrogen ions there are the lower the pH. The less hydrogen ions there are another way to look at it the more hydroxide ions there are the higher the pH. So here you see the pH scale it goes from 0 to 14. Pure water has an equal number of hydrogen ions and hydroxide ions which is why it's neutral and has a pH of 7. Anything with a pH below 7 is acidic and the lower the number the more acidic it is. Either the pH above 7 is alkaline or basic and the more alkaline or basic it is the higher the number. Alright so we talked about, yeah again we won't talk too much about how things get real nasty on both ends but you can see this by looking at this. Pure water perfectly safe. People think of acids as being dangerous like battery acid there at the bottom but look at the top. Drain cleaner, oven cleaner these are some of the most potentially dangerous compounds on the planet. So the both extremes are very very dangerous. Alright so what is the pH scale? Let's say logarithmic scale of hydrogen ion concentration. So what that means, look at anything here, something with a pH of 3 has 10 times more hydrogen ions than something with a pH of 4. Now if you're going to jump down to 2 though, so from 4 to 2 you go 10 times 10. So something with a pH of 2 would have a 100 times more hydrogen ions than something with a pH of 4. That's what it means to be this logarithmic scale. Let's see one more example here, look at urine. Urine with a pH of 6 let's say. So that means urine is 10 times more acidic than pure water or has 10 times more hydrogen ions than pure water. We jump to the bottom hydrochloric acid would be 10 million times more acidic than water or would have 10 million times more hydrogen ions than pure water. Let's see how we got there. 7 to 6 would be 10, 6 to 5 10 times 10 or 100, 5 to 4 100 times 10 to 1,000, 4 to 3, 1,000 times 10 to 10,000, 3 to 2, 10,000 times 10 to 100,000, 2 to 1, 100,000 times 10 to 1 million and then 1 to 0, 1 million times 10 to 10 million. That's why hydrochloric acid or something with a pH of 0 would be 10 million times more acidic than water. That's what it means to be a logarithmic scale. If you're traveling up then it would be 10, 100, 1,000 times less hydrogen ions. That's what it means to be an acid or a base. That's the pH scale and that's what it means when we say it's a logarithmic scale. I hope this helps. Have a wonderful day. Be blessed.