1. Acid-Base Equilibrium Chapter 18

2. Acids and Bases Arrhenius acids:generate H + in water bases:generate OH - in water Brønsted-Lowry acids:H + donors bases:H + acceptors HCl + H 2 O  Cl  + H 3 O + acid base acid base

3. H 3 O + = H + (aq) = proton in water

6. Conjugate acid-base pairs Conjugate base: remains after H + is lost acid: HClconj. base:Cl - Conjugate acid: remains after H + is gained base: NH 3 conj. acid:NH 4 + BaseAcid+ Base+ Conjugate Pair

9. Strong and Weak Acids Strong:100% dissociation good H + donor equilibrium lies far to right (HNO 3 ) generates weak base (NO 3 - ) Weak:<100% dissociation not-as-good H + donor equilibrium lies far to left (CH 3 COOH) generates strong base (CH 3 COO - )

11. Very strong Strong Weak Very weak Relative Acid Strength Relative Conj. Base Strength Very weak Weak Strong Very strong

12. Acid Dissociation Constant

14. K a Increases Strength vs. K a

15. Acid Base Conj. Acid Conj. Base Acid Base Conj. Acid Conj. Base Water is amphoteric

16. Proton Transfer in Water OH H OH H OH H OH H OH H O H H OH H OH H + - OH H O H - H OH H OH H

17. [H 3 O + ] and [OH - ] [H 3 O + ] 1x10 0 to 1x10 -14 in water [OH - ] 1x10 -14 to 1x10 0 in water

18. Finding [H 3 O + ] and [OH - ]

19. pH Scale pH 0 to 14 in water pOH 14 to 0 in water pK w = pH + pOH = 14

20. H+H+ H+H+ H+H+ OH - 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Acidic Neutral Basic pH and pOH As [H 3 O + ] rises, [OH - ] falls As pH falls, pOH rises

24. Indicators

26. Polyprotic Acids 1.H 3 PO 4 H 2 PO 4 - + H + K a1 = 7.2 x 10 -3 2.H 2 PO 4 - HPO 4 2- + H + K a2 = 6.3 x 10 -8 3.HPO 4 2- PO 4 3- + H + K a3 = 4.2 x 10 -13 K a1 > K a2 > K a3

28. Strength of Bases Strong: 100% dissociation OH - supplied to solution NaOH (s)  Na + (aq) + OH - (aq) Weak: <100% dissociation OH - by reaction with water CH 3 NH 2(aq) + H 2 O (l) CH 3 NH 2(aq) + OH - (aq)

31. Base Dissociation Constant

32. K w, K a and K b

35. Structure and Acid-Base Behavior Binary hydrides: 1.Bond polarity (high  acid strength) 2.Bond strength (low  acid strength)

37. Structure and Acid-Base Behavior Binary oxides: 1.Acidic oxides (acid anhydrides) O—X bond:strong and polar SO 2, SO 3, NO 2, P 4 O 10, … 2.Basic oxides (basic anhydrides) O—X bond:ionic K 2 O, CaO, …

38. Structure and Acid-Base Behavior Oxoacids (H a X b O c ): 1.Same number of O on different X EN of X 2.Different number of O on same X more O

39. Relative Strengths of Oxoacids

40. Cl OH Electron density ClOH Electron density O ClOH Electron density O O ClOH Electron density O O O 1 O 2 O 3 O 4 O Increasing Acid Strength

41. Lewis Acids and Bases Lewis Acid: electron pair acceptor Lewis Base: electron pair donor Acid Base