 So this problem asks us to write balanced equation to explain whether the addition of hydronium ions from a strong acid affects the solubility of copper 2-hydroxide. So in order to do this particular problem, you're going to have to know what copper 2-hydroxide is. So copper 2-hydroxide, so copper 2 is C2 plus. And of course, hydroxide's OH minus. So to combine those, we're going to have CUOH2. And that's a salt. It's a new soluble problem, or slightly salt. So what we're going to want to do is write the reaction equation, all this first thing. So when this breaks up, it goes to CU2 plus ion, plus 2OH minus, OK? So is everybody OK to the right thing? So now it says we're going to add protons to it, or hydronium ions, to this particular compound, or the solution to see if this compound becomes more soluble or not. So let's add protons to this, or hydronium. So when we do that, what happens to the, well, let's add two. What happens to the hydronium ions when we add two? Well, they make water with what? The OH. So we're going to have, what, four water molecules now, since we added two hydronium. So is everybody OK with that? So instead of having all of these hydroxides and hydroniums, we're going to erase that and have four water molecules. So was that in the original reaction equation there? So in fact, what did we do? We removed hydroxides. Does that make sense? We removed hydroxides from that equation. Because water is in our water solution already. Is everybody OK with that? So what did we do to this thing that there was hydroxides there? And we removed it. So what's going to happen to this side of the reaction? It's going to push it that way. Why? Because it needs to make more hydroxide ions to make the Ksp, the equilibrium constant, that number. So since we took away the hydroxide ions, if we add hydronium to this solution, will this increase the solubility of this particular compound here? Yes, it does. It increases the solubility. Yes. So if the protons or hydronium ions will remove that hydroxide, then it increases the solubility. Any questions on this one?