 In this video, I want to go over the term soluble and insoluble salts. First of all, what does soluble and insoluble mean? Next, the term salt. So whenever we're referring to a salt, we're talking about an ionic compound. An ionic compound forms when a cation positively charged ion and an anion, which is a negatively charged ion, come together and form a bond. This forms an ionic compound. Now your cations are going to be your metals. Metals are located on the left side of the periodic table. Your anions make up your non-metals, which are located on the right side of the periodic table. So a soluble salt is simply an ionic compound that will dissolve in a solvent such as water. An insoluble salt is the complete opposite. This is an ionic compound. Once again, you've got your positive and your negative ions, but this compound will not dissolve in water. And only a salt that contains a soluble cation or a soluble anion will dissolve in water. How do we determine if a compound is soluble or if it's insoluble? We use these solubility rules from a solubility chart in order to determine whether something is soluble or insoluble in water. What you'll see here is in this first column, we have our soluble salts. So all elements from group one or alkali metals plus your ammonium ion compounds are soluble. You'll see nitrates are also soluble, acetates are soluble with certain exceptions that being bound to silver ion. Chlorides are soluble, bromides and iodides with exceptions of silver, lead, copper and mercury. And then finally sulfates are soluble with the exception of silver, lead, barium, strontium and calcium. On the right side of the table, we have our insoluble salts. So our carbonates are insoluble except when bound to your alkali metals or ammonium ions, sulfates are insoluble, phosphates, hydroxides, oxides and sulfides are insoluble with certain exceptions. Now how do we use this solubility chart to determine if a salt is soluble or insoluble? Let's look at four examples here to help us determine if these salts are soluble or insoluble. Next one being sodium sulfate. Is sodium sulfate soluble in water or not? In order to determine if sodium sulfate is soluble, we go back to our solubility chart. What you will see here is that it tells us sulfates are soluble except when bound to silver, lead, barium, strontium or calcium. So therefore our compound sodium sulfate should be soluble because it fits into our soluble column. So it is soluble because it contains that sodium and that sulfate. The next compound magnesium carbonate. Going back to our solubility chart, magnesium carbonate made up of carbonate. Here we find carbonate in our insoluble column. It is insoluble unless it is mixed with a group 1 alkali metal, an ammonium ion or a urinal compound. Magnesium is none of those. So therefore magnesium carbonate would be insoluble. Let's look at the third compound, lead chloride. So our solubility chart tells us that chlorides are soluble with certain exceptions however. The exceptions are silver, lead, copper and mercury. Since lead is an exception, when lead chloride is bound together, that salt will be insoluble. And then finally our fourth example here, we have magnesium chloride. Magnesium chloride once again being a chloride should be soluble because it does not fit into one of those exceptions to that rule. So magnesium chloride will be soluble. Now how can we use these solubility rules to predict the outcome whenever we mix two ionic compounds together? So here we have an example of an equation where we have, we've got lead nitrate. Lead nitrate is soluble in water, which is why we have this AQ following the lead nitrate. It means it's an aqueous compound. It is soluble in water. We take lead nitrate and we mix it with sodium chloride, also a soluble compound. So we mix these two compounds together. We have two clear, colorless liquids. Both ionic compounds are soluble salts, so they mix well in water. What do we expect to happen when we mix them together? We should be able to predict this. Now before we're able to predict this, let's understand what happens when we mix a soluble ionic salt in water. Whenever you have a salt that is soluble in water, for example, sodium chloride, and you mix it in water, you do not have sodium chloride floating around in that water anymore. What happens is because of the charges on the water molecules, they will disassociate those ions from each other. So what you really have when you mix lead nitrate and sodium chloride together is you have a mixture of four separate ions floating around in your water solution. You have lead ion. You have nitrate ion, sodium, and chlorine ion. These are all floating around. Now that we kind of understand that, we can get an idea of what we expect to happen whenever we mix these two compounds together. So what we have here is we have two new combinations of ionic compounds. Originally, our lead and our nitrate were bound together. It's soluble. So when lead and nitrate come together in the solution, since it's soluble, they will come back apart. However, we also have lead and sodium. One thing you should notice though is the charge. Lead and sodium both have positive charges. If they both have positive charges, they will repel each other whenever they come in close contact with each other. However, we also have lead and chlorine, positive and a negative charge. Whenever they come together, this is a new combination of an ionic salt. So that's our first combination is lead chloride. Our next new compound is going to be sodium, positively charged sodium, and negatively charged nitrate or sodium nitrate. So what we can do now is we can go back and look at our solubility chart and determine is lead chloride soluble and is sodium nitrate soluble. What you'll remember from looking at your chart is that sodium nitrate is soluble in water. Nitrates are soluble, especially when bound to sodium. Nitrates are soluble, except for those four exceptions, copper, mercury, lead, and silver. So when lead and chlorine come together, they form an insoluble salt. So as soon as a lead and a chloride ion come together and form that bond, they form an insoluble salt so they will precipitate out of solution. Precipitate means to form a solid out of that liquid solution falls to the bottom. So we've now predicted what we expect to happen whenever we mix these two compounds together. When we mix lead, nitrate, and sodium chloride together, we get a solid form of lead chloride. Plus we get sodium nitrate, which is aqueous or a soluble salt. This is known as our full equation. Our full equation shows our new combinations of ions and whether they're aqueous or whether they're solids once they're formed. Our ionic equation shows what we see at the molecular level happening inside of that solution. So instead of having lead, nitrate, and sodium chloride, we have each ion in its separate conditions. However, whenever they're mixed together, when lead chloride comes together, forms an insoluble salt so it does not come back apart. So it stays as a solid and then we're left over with our sodium and our nitrate ions. And then finally we have our net ionic equation. Our net ionic equation just gets rid of the ions that don't play a part in the reaction. These are known as spectator ions. Spectator ions in this case would be nitrate and sodium. You see that nitrate and sodium are the same on both sides of the reactions. If you have an ion that's the same on the left and the right side, that's a spectator ion. Get rid of the spectator ions in your net ionic equation to simply show when we mix lead ion, chloride ion together, we get a solid insoluble ionic salt called lead chloride.