 The next reaction is neutralization. Remember that we know that when acids and bases meet each other, they neutralize each other's properties. But how? Let's take the example of hydrochloric acid reacting with sodium hydroxide. What happens? Well, the products are a salt and water. So where does the water come from? It's formed by the hydrogen ion from the acid bonding with the hydroxide ion from the base. This is why acids and bases neutralize each other. And once that has happened, what's left? Well, the anion from the acid, the chloride, and the cation from the base are left. And it's these that form the salt. And in this case, it is actually table salt, sodium chloride. Let's try another example. Phosphoric acid reacting with magnesium hydroxide. Okay, so the products are water again. The protons from the acid will react with the hydroxide ions to give water. I'm not worrying about balancing the equation yet, just what the products are. Okay, if we assume all the hydrogens and hydroxides are used up, what's left? The anion from the acid is phosphate, and the cation from the base is magnesium. So the salt product is magnesium phosphate. And now we can balance it.