Buffer Solution

BUFFER SOLUTION (ACID)
An acidic buffer solution is simply one which has a pH less than 7. Acidic buffer solutions are commonly made from a weak acid and one of its salts - often a sodium salt.
Objectives:
1. Measure the pH of the unknown solution first with indicators and then with pH paper. 2. compare the buffer solution with both a strong acid and a weak acid

materials:
2 30 mL beakers
2 100mL volumetric flask
1 10mL pipet
2 aspirator
1 50mL graduated cylinder
1 10mL graduated cylinder
1 50mL beaker
1 100 mL beaker
1 glass stir rod
1 ring stand
1 clamp
1 250mL beaker
Distilled water pH paper

reagents:
10mL 6M acetic acid
10g solid sodium acetate
25mL 1M naOH
NH3
NH4Cl 0.1 solution

Safety:
Acetuc acid, HCl and NaOH are corrosive. They attact the skin and cause permanent damage to the eyes. If one of these solutions splashes into your eyes, use the eyewash immediately. Hold your eyes open and flush with water. If contact with skin or clothing occurs, flush the affected area with water.
Procedure:
1. using the 10mL volumetric pipet and a 100.0 mL volumetric flask, preparte 100.0 mL of 0.60 M acetic acid by diluting in water. 2. Using the other 100 mL volumetric flask, prepare 50 mL of 0.60 M sodium actatate solution by dissolving solid sodium acttae in water and diluting to a total volume of 50 mL 3. Use the graduated cylinder to measure 30 mL of 0.60 M acetic acid solution you prepared into a 50mL beaker. Measure the pH of this solution using the pH paper. 4. Add 10 mL of your sodium acetate solution to the beaker containing acetic acid and stir with a clean stirring rod. Measure pH of the solution and record it. 5. Add 10mL of your actic acid solution to the beaker containing sodium acetate and stir with clean stirring rod. Measure pH of the solution. 6. Make solution by mixing 10 mL ofacetic acid solution with 10mL of sodium acetate, stirring well. Measure the pH and record.

BUFFER SOLUTION (base)
An acidic buffer solution is simply one which has a pH less than 7. Acidic buffer solutions are commonly made from a weak acid and one of its salts - often a sodium salt.
Objectives:
3. Measure the pH of the unknown solution first with indicators and then with pH paper. 4. compare the buffer solution with both a strong acid and a weak acid materials: 2 30 mL beakers
2 100mL volumetric flask
1 10mL pipet
2 aspirator
1 50mL graduated cylinder
1 10mL graduated cylinder
1 50mL beaker
1 100 mL beaker
1 glass stir rod
1 ring stand
1 clamp
1 250mL beaker
Distilled water pH paper

reagents:
10mL 6M NH4Cl
10g solid sodium acetate
25mL 1M naOH
NH3
NH4Cl 0.1 solution

Procedure: 7. using the 10mL volumetric pipet and a 100.0 mL volumetric flask, preparte 100.0 mL of 0.60 M NH4Cl by diluting in water. 8. Using the other 100 mL volumetric flask, prepare 50 mL of 0.60 M sodium acetate solution by dissolving solid sodium acetate in water and diluting to a total volume of 50 mL 9. Use the graduated cylinder to measure 30 mL of 0.60 M acetic acid solution you prepared into a 50mL beaker. Measure the pH of this solution using the pH paper. 10. Add 10 mL of your sodium acetate solution to the beaker containing NH4Cl and stir with a clean stirring rod. Measure pH of the solution and record it. 11. Add 10mL of your NH4Cl solution to the beaker containing sodium acetate and stir with clean stirring rod. Measure pH of the solution. 12. Make solution by mixing 10 mL Nh4Cl solution with 10mL of sodium acetate, stirring well. Measure the pH and record.