Consider the following titration curve for a 1.0 M solution of a diprotic acid, H
2As with NaOH.
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What are the approximate pH values at points 1,2,3,4?
Here's what I already have.. the major species at point;
1. H
2As, HAs-
2. HAs-
3. HAs-, As
2-
4. As
2-
and the pH values at points;
1. 4.10
2. 7.95
3. 11.79
4. ?? This is the one I'm having problems with. I was told to use K
b values so I set up K
b = K
w/K
a, what do I do with that value(s) though?
THANKS SO MUCH!!
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