Determine the Concentration of the Unknown Strong Acid, perform a titration using and phenolphthalein found in the virtual lab. (Note: The concentration of the acid is between 0.025M and 2.5M so you will need to dilute the NaOH solution so that the volume to reach the endpoint is between 10 and 50 mL).

 

Answer:

Step 1. Prepare a 100 mL solution of NaOH with 0.25 Molarity. Take 2.5 mL of the given NaOH solution (10M) and dilute it to 100 mL. You will have 0.25 M 100 mL NaOH solution. Fill this in the burette and note down the reading.

Step 2. Take around 25 mL unknown solution in a flask and add few drops of phenolphthalein as an indicator.

Step 3. After completion of titration, note down the total amount of NaOH solution added.

Step 4. Calculate the concentration of unknown acid.

Molarity of acid = molarity of base x volume of base / volume of acid