Question

You will be standardizing the stock lab solution of NaOH (which is approximately 0.3M) by reacting it with a carefully measured sample of potassium hydrogen phthalate (KHP). Outline the steps or procedure you would follow for this standardization process.

Answer 1

The steps for standardizing the NaOH solution with KHP include weighing a sample of KHP, dissolving it in water, adding phenolphthalein indicator, titrating with NaOH, and calculating the molar concentration.

Step-by-step explanation:

The steps for standardizing the stock lab solution of NaOH by reacting it with potassium hydrogen phthalate (KHP) are as follows:

1. Weigh a sample of KHP.
2. Dissolve the KHP in a measured amount of distilled water.
3. Add a few drops of phenolphthalein indicator to the KHP solution.
4. Titrate the KHP solution with the NaOH solution until a light pink color persists for at least 30 seconds.
5. Record the volume of NaOH solution used for the titration.
6. Repeat the titration two more times to ensure accuracy.
7. Calculate the molar concentration of the NaOH solution by using the volume of NaOH solution used and the mass of KHP.