by Bipolarity
P: 783
 Quote by Borek How many decimal digits in your "7"?
When my calculator evaluated a pH of 7, I think it was about 9-10 decimal places, so something like 7.000000000

I am pretty sure the result was exactly 7. Not completely sure, but I think if I ran it on Maple with 50 s.f. it would come out to be 7.000000000000000000000000000000000000000000000000000000000000000000000 0

I will recheck and let you know. Have you done the problem?

Thanks by the way.

BiP

 Admin P: 23,731 Titration Paradox! No, I have not done the problem, but I know what to expect. Your answer (zillions of zeros) is wrong. Show how you got it.
P: 21
You probably did a numerical error in the total volume, but that's not important, still you get closer to 7 than you actually should. There is more fundamental fallacy behind the calculation. You rely too much on the simplified equation pH = -log c (or pOH = -log c in the basic case). This equation does not account for the ions from dissociation of water which become relevant in very dilute solutions.