1. Buffer Solutions Buffer solutions are equilibrium systems, which maintain a relatively constant pH when small amounts of acids or bases are added. Acid Buffer Recipe Weak Acid + Salt (conjugate) HF NaF Buffer EquationSame as weak acid HF ⇋ H + +F -

2. Buffer Solutions Buffer solutions are equilibrium systems, which maintain a relatively constant pH when small amounts of acids or bases are added. Acid Buffer Recipe Weak Acid + Salt (conjugate) HF NaF Buffer EquationSame as weak acid HF ⇋ H + +F - [High]

3. Buffer Solutions Buffer solutions are equilibrium systems, which maintain a relatively constant pH when small amounts of acids or bases are added. Acid Buffer Recipe Weak Acid + Salt (conjugate) HF NaF Buffer EquationSame as weak acid HF ⇋ H + +F - [High][low]

4. Buffer Solutions Buffer solutions are equilibrium systems, which maintain a relatively constant pH when small amounts of acids or bases are added. Acid Buffer Recipe Weak Acid + Salt (conjugate) HF NaF Buffer EquationSame as weak acid HF ⇋ H + +F - [High][low] [High]

5. Buffer EquationSame as weak acid HF ⇋ H + +F - [High][low][High] The [HF] is relatively high because HF is a weak acid and does not dissociate very much. The [H + ] is low for the same reason. The [F - ] is high due to adding the salt NaF to the solution. This buffer solution has high concentrations of HF and F -, which means it has the ability to shift left or right and maintain the H + concentration and hence the pH remains at a relatively constant level.

6. 1.0 M HCN is mixed with 2.0 M NaCN to make a buffer solution. Write the equation for the buffer solution. Determine the [HCN] and [CN - ]. HCN ⇋ H + +CN - 1.0 M

7. 1.0 M HCN is mixed with 2.0 M NaCN to make a buffer solution. Write the equation for the buffer solution. Determine the [HCN] and [CN - ]. HCN ⇋ H + +CN - 1.0 MLow

8. 1.0 M HCN is mixed with 2.0 M NaCN to make a buffer solution. Write the equation for the buffer solution. Determine the [HCN] and [CN - ]. HCN ⇋ H + +CN - 1.0 MLow2.0 M

9. Base Buffer Recipe Weak Base +Salt (conjugate) NH 3 NH 4 Cl Buffer EquationSame as weak base NH 3 +H 2 O ⇋ NH 4 + +OH -

10. Base Buffer Recipe Weak Base + Salt (conjugate) NH 3 NH 4 Cl Buffer EquationSame as weak base NH 3 +H 2 O ⇋ NH 4 + +OH - [High]

11. Base Buffer Recipe Weak Base + Salt (conjugate) NH 3 NH 4 Cl Buffer EquationSame as weak base NH 3 +H 2 O ⇋ NH 4 + +OH - [High]

12. Base Buffer Recipe Weak Base + Salt (conjugate) NH 3 NH 4 Cl Buffer EquationSame as weak base NH 3 +H 2 O ⇋ NH 4 + +OH - [High][High][Low]

13. Fill in the blanks to get buffer solutions. AcidBase HCN

14. Fill in the blanks to get buffer solutions. AcidBase HCN NaCN

15. Fill in the blanks to get buffer solutions. AcidBase HCN NaCN NaHCO 3

16. Fill in the blanks to get buffer solutions. AcidBase HCN NaCN H 2 CO 3 NaHCO 3

17. Fill in the blanks to get buffer solutions. AcidBase HCN NaCN H 2 CO 3 NaHCO 3 H 3 PO 4

18. Fill in the blanks to get buffer solutions. AcidBase HCN NaCN H 2 CO 3 NaHCO 3 H 3 PO 4 NaH 2 PO 4

19. Fill in the blanks to get buffer solutions. AcidBase HCN NaCN H 2 CO 3 NaHCO 3 H 3 PO 4 NaH 2 PO 4 KCH 3 COO

20. Fill in the blanks to get buffer solutions. AcidBase HCN NaCN H 2 CO 3 NaHCO 3 H 3 PO 4 NaH 2 PO 4 CH 3 COOHKCH 3 COO

21. Fill in the blanks to get buffer solutions. AcidBase HCN NaCN H 2 CO 3 NaHCO 3 H 3 PO 4 NaH 2 PO 4 CH 3 COOHKCH 3 COO NH 4 Cl

22. Fill in the blanks to get buffer solutions. AcidBase HCN NaCN H 2 CO 3 NaHCO 3 H 3 PO 4 NaH 2 PO 4 CH 3 COOHKCH 3 COO NH 4 ClNH 3

23. Fill in the blanks to get buffer solutions. AcidBase HCN NaCN H 2 CO 3 NaHCO 3 H 3 PO 4 NaH 2 PO 4 CH 3 COOHKCH 3 COO NH 4 ClNH 3 Na 2 CO 3

24. Fill in the blanks to get buffer solutions. AcidBase HCN NaCN H 2 CO 3 NaHCO 3 H 3 PO 4 NaH 2 PO 4 CH 3 COOHKCH 3 COO NH 4 ClNH 3 NaHCO 3 Na 2 CO 3

25. Fill in the blanks to get buffer solutions. AcidBase HCN NaCN H 2 CO 3 NaHCO 3 H 3 PO 4 NaH 2 PO 4 CH 3 COOHKCH 3 COO NH 4 ClNH 3 NaHCO 3 Na 2 CO 3 NaH 2 PO 4

26. Fill in the blanks to get buffer solutions. AcidBase HCN NaCN H 2 CO 3 NaHCO 3 H 3 PO 4 NaH 2 PO 4 CH 3 COOHKCH 3 COO NH 4 ClNH 3 NaHCO 3 Na 2 CO 3 NaH 2 PO 4 Na 2 HPO 4

27. Buffer Application 1.Pick the two buffer solutions A.NH 4 Cland HCl B.NaClandNaOH C.HFandNaF D.NH 4 ClandNH 3

28. Buffer Application 1.Pick the two buffer solutions A.NH 4 Cland HCl B.NaClandNaOH C.HFandNaF D.NH 4 ClandNH 3

29. Buffer Application 1.Pick the two buffer solutions A.NH 4 Cland HCl B.NaClandNaOH C.HFandNaF D.NH 4 ClandNH 3 2.Write the equations for the above two buffer solutions. Label each species in the equation as high or low concentration.

30. Buffer Application 1.Pick the two buffer solutions A.NH 4 Cland HCl B.NaClandNaOH C.HFandNaF D.NH 4 ClandNH 3 2.Write the equations for the above two buffer solutions. Label the each species in the equation as high or low concentration. HF ⇋ H + +F - NH 3 +H 2 O=NH 4 + +OH -

31. Buffer Application 1.Pick the two buffer solutions A.NH 4 Cland HCl B.NaClandNaOH C.HFandNaF D.NH 4 ClandNH 3 2.Write the equations for the above two buffer solutions. Label the each species in the equation as high or low concentration. HF ⇋ H + +F - [High] [Low] [High] NH 3 +H 2 O=NH 4 + +OH -

32. Buffer Application 1.Pick the two buffer solutions A.NH 4 Cland HCl B.NaClandNaOH C.HFandNaF D.NH 4 ClandNH 3 2.Write the equations for the above two buffer solutions. Label the each species in the equation as high or low concentration. HF ⇋ H + +F - [High] [Low] [High] NH 3 +H 2 O=NH 4 + +OH - [High] [High] [Low]

33. 3.A few drops of 0.10 M NaOH is added to a buffer solution at pH = 5.00. The new pH could be: A4.98 B.5.02 C.8.05 D.2.11

34. 3.A few drops of 0.10 M NaOH is added to a buffer solution at pH = 5.00. The new pH could be: A4.98 B.5.02 C.8.05 D.2.11

35. Indicators Methyl violet HInd ⇋ H + +Ind - AcidBase

36. Indicators Methyl violet HInd ⇋ H + +Ind - AcidBase YellowBlue

37. Indicators Methyl violet HInd ⇋ H + +Ind - AcidBase YellowBlue ShiftColour At pH < 0.8

38. Indicators Methyl violet HInd ⇋ H + +Ind - AcidBase YellowBlue ShiftColour At pH < 0.8Left

39. Indicators Methyl violet HInd ⇋ H + +Ind - AcidBase YellowBlue ShiftColour At pH < 0.8LeftYellow

40. Indicators Methyl violet HInd ⇋ H + +Ind - AcidBase YellowBlue ShiftColour At pH [Ind - ]

41. Indicators Methyl violet HInd ⇋ H + +Ind - AcidBase YellowBlue ShiftColour At pH [Ind - ] At pH > 0.8

42. Indicators Methyl violet HInd ⇋ H + +Ind - AcidBase YellowBlue ShiftColour At pH [Ind - ] At pH > 0.8Right

43. Indicators Methyl violet HInd ⇋ H + +Ind - AcidBase YellowBlue ShiftColour At pH [Ind - ] At pH > 0.8RightBlue

44. Indicators Methyl violet HInd ⇋ H + +Ind - AcidBase YellowBlue ShiftColour At pH [Ind - ] At pH > 0.8RightBlue[HInd] < [Ind - ]

45. Indicators Methyl violet HInd ⇋ H + +Ind - AcidBase YellowBlue ShiftColour At pH [Ind - ] At pH > 0.8RightBlue[HInd] < [Ind - ] At pH = 0.8

46. Indicators Methyl violet HInd ⇋ H + +Ind - AcidBase YellowBlue ShiftColour At pH [Ind - ] At pH > 0.8RightBlue[HInd] < [Ind - ] At pH = 0.8Middle

47. Indicators Methyl violet HInd ⇋ H + +Ind - AcidBase YellowBlue ShiftColour At pH [Ind - ] At pH > 0.8RightBlue[HInd] < [Ind - ] At pH = 0.8MiddleGreen

48. Indicators Methyl violet HInd ⇋ H + +Ind - AcidBase YellowBlue ShiftColour At pH [Ind - ] At pH > 0.8RightBlue[HInd] < [Ind - ] At pH = 0.8MiddleGreen[HInd] = [Ind - ]

49. @ the transition point Ka = [H + ] Ka = 10 -pH Ka = 10 -0.8 = 0.2