This preview shows pages 1–3. Sign up to view the full content.
This preview has intentionally blurred sections. Sign up to view the full version.
View Full Document
Unformatted text preview: + donation : H 3 A Three equilibria : k a1 , k a2 , k a3 Example : H 3 PO 4 Diprotic Acids H 2 A(aq) + H 2 O(l) H 3 O + (aq) + HA (aq) K a1 HA (aq) + H 2 O(l) H 3 O + (aq) + A 2 (aq) K a2 H 2 A H 3 O + HA A 2 [Initial] a 0 0 [Change] x +x+y +xy +y [Equilib.] ax +x+y +xy +y Double Equilibrium Two equations two unknowns K a1 = K a2 = Can simplify when K a2 << K a1 Use weak acid approach and proceed stepwise. x 2 y 2 a x y (x + y) x y 3 Example Calculate the pH of a 0.1 M solution of H 2 S given that K a1 = 1.3 x 10 7 and K a2 = 7.1 x 10 15 . Example Calculate the concentration of all components of a 0.01 M H 3 PO 4 solution given that K a1 = 7.6 x 10 3 , K a2 = 6.2 x 10 8 , and K a3 = 2.1 x 10 13 ....
View
Full
Document
This note was uploaded on 04/23/2008 for the course CHEM 2B taught by Professor Clemens during the Winter '08 term at UC Davis.
 Winter '08
 Clemens
 Bases

Click to edit the document details