posted by bill on .
When titrating a strong acid with a strong base, which is true?
1. the titration curve slopes upward
2. an indicator that changes at pH 8 would be acceptable
3. the pH changes slowly at the equivalence point
For any titration you want a sharp change in pH at the equivalence point; therefore, you KNOW #3 can't be right.
I'm not sure what #1 means but I would assume sloping upward would mean a more or less gradual change from beginning to end; therefore, I wouldn't pick #1.
The equivalence point for the titration of a strong acid with a strong base is at pH = 7.0. Most indicators are good over a range of pH = 2 so an indicator changing at pH = 8.0 should be ok.
So, in one of those titration curves, when it looks like it is stretched out with one side sloping down and the other up, is that representing titration with a weak acid or base?
Here is a typical titration curve. Scroll down about half way on the page.