Purpose of the lab: To find the (pH) and the molarity (M) of acids in a substance.

Materials: 

Candy (Blue Powder – Citric Acid) 10g.

(2) 50mL Beakers (H20) and (0.1M NaOH).

Drops of Phenolphthalein (C20H14O4).

A Flask.

a 10 mL measuring tube.

Funnel.

Burette.

Titration Stand w/ clamp.

Procedure:

1.) Weight out (10g) of candy (citric acid) on the scale.

2.) Combine the candy with H20 so the candy dissolves.

3.) Pour (10mL) of (water + citric acid) solution into the flask.

4.) Place 3-4 drops (C20H1404) in the flask.

5.) Carefully pour NaOH into the burette. Make sure the starting levels at 0.

6.) Slowly drop NaOH into the flask with your previous solution, once a color change is apparent, stop the flow of the NaOH.

7.) Recording and keep recording the quantity of NaOH that was added to the solution.

Photos: 

Results and Calculations:

Analysis:

My partner and my’s result was very close to the actual pH of citric acid as we got a pH of 3.13 and the actual pH was 3.2, the reason it was so close is that the pieces of blue powder were able to dissolve to make our solution very pure. Reasons, why our resulting pH was not exact, was that the particles did not dissolve completely. Another reason why our pH’s didn’t perfectly align is that we may have added more NaOH to the solution in the flasks, accuracy played a vital part in our results and we could have tried to be more precise in our procedure.