 Now we need a couple more steps in order for us to actually quantify this. So let's look at this stage to see if we've got some general rules we can use. There's variations on these rules and it doesn't really matter which ones you pick as long as you have a way of remembering some of these key solubility rules. So the first thing we want to look at is NAGSAG. Nitrates, acetates, group 1 ions, and we used two of those on the previous slide. We said that all nitrates are soluble. So that's important. Acetates, that's the ion that has two carbons, a double bonded oxygen and anome minus, which is the anion of acetic acid or ethanoic acid. They're always soluble and the group 1 ions are always soluble. So that's sodium, lithium, potassium, etc. The SAG part is sulfates, ammonium, and the group 7. Now, when we get to these ones, except for ammonia, ammonia is a nice easy one because ammonium ions are always soluble. But for the sulfates and the group 7, they are always soluble except there are some exceptions. So the NAGSAG of the general rules and our LMS castrobar are our exceptions. So if we look at the sulfates, we can see that all of the sulfates are soluble with two groups of exceptions. The first group of exceptions are our LMS, our lead ions, our mercury ions, and our silver ions, LMS. So that means that when we say sulfates are always soluble except these, that would mean lead sulfate is insoluble. It would form a precipitate and so would silver sulfate and so would mercury. Now, this also has an exception for the castrobar. The castrobar is calcium, strontium, barium. These are group 2 metals. And so they're an important group as well. Calcium, sulfate, strontium sulfate, and barium sulfate, each of these are also insoluble. So we have our general rules and then we look at our exceptions. Barium sulfate would form a solid. In the group 7 elements, all anions, each of these is also soluble. The exception again is the LMS group. So that means that silver chloride, chlorine is one of our group 7 elements. They're all soluble, but since silver chloride is an exception, it will fall into that insoluble group. It'll take a little practice for you to do this. And of course, I haven't talked about carbonates, phosphates, hydroxides, any of those yet. And because they're not on the soluble list, you can assume they are insoluble, but again, there's some exceptions. This is a bit of a complex area of chemistry and some little tricks to help you remember are very important. So make sure you practice. And just a quick shout out to Reese. Thanks for watching.