Ascorbic acid, H2C6H6O6, is a diprotic acide with a K1= 7.9 E-5 and a K2=1.6E-12. In a .005 M aq solution of ascorbic acid which of the following species is present in the lowest concentration.

Question

Ascorbic acid, H2C6H6O6, is a diprotic acide with a K1= 7.9 E-5 and a K2=1.6E-12. In a .005 M aq solution of ascorbic acid which of the following species is present in the lowest concentration. 
1. H2O
2. H3O
3. H2C6H6O6
4. HC6H6O6
5. C6H6O6

DrBob222 · Answer

You didn't put charges on what you wrote. The way you work this problem is to write the ionization of the two hydrogens and the k1 and k2 expressions. Then some reasoning ability to see which one is the least. k1 and k2 are given so logic will tell you.