Methods:

1. Weigh out 4.2 g of NaOH and dissolve it quickly in about 50 mL water in a 250 mL Erlenmeyer flask.

2. Transfer the solution into a 1-L volumetric flask and fill the flask to the 1000 mL mark with deionized water.

3. Seal the flask with its stopper, invert the flask, and shake it gently. Then vent the flask.

4. Transfer the solution into a 1-L plastic bottle and close it. Label the bottle properly.

5. Start a new experiment on the data collection system.

6. Connect the pH sensor and the Rotary Motion sensor to the data collection system.

7. Set up the Titrator pump, and rinse the syringe on the Titrator pump.

8. Calibrate the pH sensor using the two buffer solutions and the data collection system.

9. Add the micro stir bar to the end of the pH sensor.

10. Load the syringe on the pump with the titrant solution and prime the pump on the Titrator.

11. Measure about 0.200 g of KHP to the nearest milligram.  Then wash the KHP sample from the weighing dish with about 50mL of water, into a 180-mL titration jar. Prepare 3 samples.

12.  Add enough deionized water to the solution so the top of the pH sensor is covered with solution.

13. Turn on the magnetic stirrer at a steady rate, and start recording on the dtat collection system until the titration is past the equivalence point and the pH curve flattens.

14. Repeat Step 13 for two more KHP samples.

15. Clean the syringe in the Titrator.

Equipment:

• Data Collection System
• Titrator with syringe
• pH sensor
• Drop counter with micro stir bar
• Magnetic stirrer
• Beaker (2), 100-mL
• Beaker (2), 10-mL
• Volumetric flask, 100-mL
• Buret, 50-mL
• Buret Clamp
• Clamp, right-angle
• Funnel
• Potassium hydrogen phthalate (KHP), 0.6 g
• Sodium hydroxide (NaOH), 0.40 g
• Buffers, pH 4 and pH 10, 10mL
• Water, deionized, 250 mL
• Wash bottle with deionized water
• Parafilm
• Kim wipes