10. Take a photo of the plate showing theA Buffering Capacity of a Solutioncolors in each well.11. Empty the plate into the sink with running1. Turn the well plate 90 so that it is four rowswater. Rinse the plate with pure water, notby six columns.tap water.2. In the cup labeled “4.7,” prepare 20 mL of12. Dry the plate by placing it upside down on4.7 pH buffer by doubling the volumessome paper towels. Tap it several times tocalculated in the prelab.remove most of the water.3. Add 2 ml of this solution into all 6 wells in the13. Set aside the water, acetic acid, sodiumfirst row. See Figure 3 below.acetate, and sodium hydroxide solutions.4. Dilute 5 mL of the 4.7 pH buffer solutionYou will need them for the next part of thewith 15 mL of purified water containing theactivity.indicator and pour into a clean cup. This is14. Empty the remaining plastic cups into thethe first dilution.sink with running water.5. Add 2 mL of the first dilution to all the wells inthe second row.Figure 3.Un-diluted bufferOooOOOFirst dilutionOooOOOSecond dilutionOOOOOOThird dilutionOooOOOcontinued on next pageCAROLINAwww.carolina.com/distancelearning 9

10. Take a photo of the plate showing theA Buffering Capacity of a Solutioncolors in each well.11. Empty the plate into the sink with running1. Turn the well plate 90 so that it is four rowswater. Rinse the plate with pure water, notby six columns.tap water.2. In the cup labeled “4.7,” prepare 20 mL of12. Dry the plate by placing it upside down on4.7 pH buffer by doubling the volumessome paper towels. Tap it several times tocalculated in the prelab.remove most of the water.3. Add 2 ml of this solution into all 6 wells in the13. Set aside the water, acetic acid, sodiumfirst row. See Figure 3 below.acetate, and sodium hydroxide solutions.4. Dilute 5 mL of the 4.7 pH buffer solutionYou will need them for the next part of thewith 15 mL of purified water containing theactivity.indicator and pour into a clean cup. This is14. Empty the remaining plastic cups into thethe first dilution.sink with running water.5. Add 2 mL of the first dilution to all the wells inthe second row.Figure 3.Un-diluted bufferOooOOOFirst dilutionOooOOOSecond dilutionOOOOOOThird dilutionOooOOOcontinued on next pageCAROLINAwww.carolina.com/distancelearning 9