1. Standardize NaOH solution with KHP
1. Pipet 40.00 ml of KHP solution into 100-ml beaker and place the magnetic bar inside the beaker.
2. Add a few drops of phenolphthalein indicator.
3. Place the beaker on the stirring plate.
4. Position the electrode so that the bulb is in the solution but above the stirring bar.
5. Record the initial pH, and initial volume of NaOH.
6. Add aliquot of 1 ml of NaOH into the breaker, record the pH and the volume of NaOH from burette.
7. Repeat the NaOH adding (1 ml each time) until pH of solution is constant around 11-12 (5 points constantly). Record the used volume of NaOH, do not allow the NaOH to go below 50.00 ml on the burette.
8. Repeat the experiment for 1-7 again, but the volume of sodium hydroxide should be changed to be 0.5 ml while the pH of solution is increased rapidly.
9. Plot graph between the pH (y-axis) VS volume of NaOH (x-axis) as same the Figure 3-1. Mark the end point of the titration on the graph.
10. Calculate the concentration of NaOH.