Phenolphthalein turns pink in solutions that are roughly 1.0 x 10^-5 M in hydrox

Question

Phenolphthalein turns pink in solutions that are roughly 1.0 x 10^-5 M in hydroxide ions. The only source of hydroxide ions is your Ca(OH)2. Let's assume that the amount of water left behind in the beaker to test for complete transfer is about three drops or .15 mL. a) How many moles of Ca(OH)2 would be present in those three drops if the solution just barely turned pink? How many grams of Ca(OH)2? b) What % of the solution/solid was transferred over to the container?
I already answered A) I got 1.5x10^-9 moles and 2.0x10^-11 g I'm stuck with the second part.

Explanation / Answer

For phenolphthalein indicator turning pink in basic medium.

Ca(OH)2 is the source of base [OH-] in solution.

b) % of solution/solid transferred = [0.15 ml solution/2 x 10^-11 g Ca(OH)2] x 100

                                                     = 7.5 x 10^11

Value for Ca(OH)2 in three drops is taken from section a).

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