So we want to use the formula for a PH. But before we use that formula, we have to find the molarity of our solution. And the way we find molarity is first we want to find the molecular weight of our solid, but then we want to find the moles of our solid. And finally we find the kilograms of solvent. We divide moles of solid by kilograms of solvent. We get molarity, plug that into our PH formula, and we find our result.