 So there's a couple of different types of reactions that you need to be aware of in this topic, ones that involve either acids or bases, and in this case both. This is one of two examples of neutralization reactions that we're going to be looking at in this particular topic, and there's going to be quite a lot more that we'll look at in depth as we roll through the different components of this particular module. For now, we just want a quick review of the basics of acid and base reactions and to start delving a little bit more into things like net ionic equations. So the first thing that we need to do is we need to look at the general equation, and in general the equation for a neutralization reaction is an acid plus a base produces a salt plus water, and it's the water that is the product that tells us that it's a neutralization reaction. So if we have substances that are not pH neutral, but we produce water, then that's an example of a neutralization reaction. Now the final solution may not always be neutral pH, but there's reasons why that might be the case, and we'll look at that later on. So let's have a look at a specific example, such as hydrochloric acid and sodium hydroxide. So in this case, we have HCl, which is going to be in solution, and it's going to combine with NaOH, which is also going to be in the solution, and we're going to form water, which is a liquid, and we're going to form a salt, and the salt that we're going to form is going to be a combination of the cation associated with the base and the anion associated with the acid. So NaCl, when we form these salts, it's probably also good for you at this stage to refer back to your solubility rules, and of course, when we start going through our little NAG sags, we realize that sodium is a group one middle and they're all soluble, so that makes this a nice easy one to determine whether or not it's soluble, and of course sodium chloride is. So here's a specific example where we have water and the salt is sodium chloride. But if the sodium chloride is soluble, then that means that some of the ions that we have in this particular reaction are going to remain in the solution, they're actually going to be spectator ions. So when we're looking at neutralization reactions, we can also develop a net ionic equation. So let's pull this whole equation apart and see what we have left. If we look at the HCl, that's going to ionize in the solution, so it's going to form H+, and Cl-. I'm going to assume these are all aqueous, and I'm sure if I was doing an exam right aqueous underneath each one, but I just for now want to try and give you an overview. So let's look at the sodium ions and the hydroxide ions that are going to come from the sodium hydroxide. And then what we're going to do is form water. Now water is not an ionic substance, it's a liquid. But the sodium chloride is also a soluble ionic substance, and therefore it's going to be there as well. Now we know that where we have spectator ions, we can eliminate them from both sides of our equation. So we've got Cl- here and Cl- here, and an Na+, here and an Na+, here. What this does is it leaves us with a net ionic equation of H+, plus OH- giving H2O liquid. And this is our neutralization reaction. Interestingly enough, there's no in the net ionic equation, the salts have become spectator ions, so they're not relevant to this part at all. So let's do one more example to see if that is the case for more than just this special case.