are going to do this at the equivalence point. Lets think about what the pH at the equivalence
point should be. At the equivalence point we will just have consumed all of the acid
and all of the base. And we would have converted it to BH+ and BH+ is what? It is an acid.
And as an acid it should have a pH below 7. So we will keep that in mind and make sure
we have a pH below 7 when we are finished. So we need to put into our ICF table what?
Well, moles. So we have to put moles in. Now they did not give me a volume to use,
so we can choose any volume. The pH at the equivalence point is the same whether you
a big vat of it, or a small quantity of it. So I am just going to choose a quantity. I
am going to choose that I am going to have in my flask, 10 ml
of that acid. Now if we are at the equivalence point we are going to have equal moles not
equal volume, not equal molarities but equal moles. So we will worry about the volume of
the base that we need to add here in just a minute. But lets take the 10 ml of the strong
acid. So to obtain the moles of H_3O+. It would be the same as the moles of that strong
acid. And that would be the molarity times the volume, I and I choose 10 ml. And