Assume that 30.0 mL of a 0.10 M solution of a weak base B that accepts one proton is titrated with a 0.10 M solution of the monoprotic strong acid HA. (a) How many moles of HA have been added at the equivalence point?

Video transcript

Hello everyone in this video, we're going to go ahead and calculate the amount of H. A needed to reach the equivalence point. So in the reaction we have a weak base going on and an acid a strong acid. So our key word here in this problem is going to be the equivalence point. So at equivalence point I'll go ahead and just put that or simplify that as E. P. So at the equivalence point we should know that our moles of acid is equal to the moles of base. And of course remembering the components of our unit of concentration capital M. That's going to be moles over liters and we'll break that up. Okay, so let's go ahead and do some quick conversions to get our molds of base which again will equal to the molds of acid at the equivalence point. So starting off with our calculation, we have the 50 ml of the solution of B. I want to go ahead and convert this into leaders. So I'm gonna do that is we have leaders on top and middle layers on the bottom. So you see that that unit of middle leaders will cancel. Then what I'm gonna do next is use the concentration unit. So again we have moles over leaders. So that's going to be 0.20 moles Over one leader. And of course the leader units will cancel. So putting all these numerical values into my calculator, I would get that the most base will equal to 0.010 moles. And because like I said at equivalence point, the most acid will equals to the Mold base. This this calculation for our most base is actually going to be the most of our strong acid. So to write the answer clearly moles Of HAR strong acid is equal to 0.010. And this right here is going to be my final answer for this problem. Thank you all so much for watching.