Titration Analysis of Aspirin Tablets
Chemistry 12
12/Oct/2011
Titration- Analysis of Aspirin Tablets
Objective: Determine the percentage of aspirin (acetylsalicylic acid) present in two different commercial tablets by titrating the solution with a base. Also determine whether the aspirin is a strong or weak acid according to the Bronsted- Lowry and Lewis theories and deduce the formula of the acid- base reaction.
Independent Variable: The amount of base (NaOH) in moles that are needed to neutralize the solution.
Dependent Variable: Percentage of aspirin (acetylsalicylic acid) found in each tablet.
Materials:
* Balance * 2 aspirin samples from different brands * 50 cm3 conical flask * 10.00cm3 of 95% alcohol * 0.100 mol dm-3 sodium hydroxide * Phenolphthalein
Procedure:
1. Bring samples of two different aspirin brands, note names, price, and the value of the aspirin per tablet indicated by the manufacturer. 2. Weight out accurately one tablet into a 50 cm3 conical flask and dissolve it in 10.0cm3 of 95% alcohol. 3. Titrate with 0.10 mol dm-3 sodium hydroxide solution using two drops of phenolphthalein solution as indicator in the first trial. 4. For the next trials repeat steps 1 and 2, but instead of using an indicator use an electronic pH tester to measure the pH of the solution to determine when its neutral; (PH -7) . 5. Record data, ml used in titration to neutralize every aspirin trial.
Raw Data Collection:
Quantitative Data:
Aspirin A: Trial | Aspirin Tablet | Uncertainty (ml) | Burette Reading NaOH(ml) | Resulting | Uncertainty (ml) | | (Grams) | | Initial (ml) | Uncertainty(ml) | Final (ml) | Uncertainty(ml) | NaOH (ml) | | 1 | 0.598 | -+0.001gr | 13.50 | -+0.05ml | 40.60 | -+0.05ml | 27.10 | -+0.10ml | 2 | 0.603 | -+0.001gr | 11.90 | -+0.05ml | 40.80 | -+0.05ml | 28.90 | -+0.10ml | 3 | 0.599 | -+0.001gr | 9.50 | -+0.05ml | 37.40 | -+0.05ml | 27.90 | -+0.10ml | Average: | 0.600 | -+0.001gr | 11.63 | -+0.05ml | 39.60 | -+0.05ml | 27.97
12/Oct/2011
Titration- Analysis of Aspirin Tablets
Objective: Determine the percentage of aspirin (acetylsalicylic acid) present in two different commercial tablets by titrating the solution with a base. Also determine whether the aspirin is a strong or weak acid according to the Bronsted- Lowry and Lewis theories and deduce the formula of the acid- base reaction.
Independent Variable: The amount of base (NaOH) in moles that are needed to neutralize the solution.
Dependent Variable: Percentage of aspirin (acetylsalicylic acid) found in each tablet.
Materials:
* Balance * 2 aspirin samples from different brands * 50 cm3 conical flask * 10.00cm3 of 95% alcohol * 0.100 mol dm-3 sodium hydroxide * Phenolphthalein
Procedure:
1. Bring samples of two different aspirin brands, note names, price, and the value of the aspirin per tablet indicated by the manufacturer. 2. Weight out accurately one tablet into a 50 cm3 conical flask and dissolve it in 10.0cm3 of 95% alcohol. 3. Titrate with 0.10 mol dm-3 sodium hydroxide solution using two drops of phenolphthalein solution as indicator in the first trial. 4. For the next trials repeat steps 1 and 2, but instead of using an indicator use an electronic pH tester to measure the pH of the solution to determine when its neutral; (PH -7) . 5. Record data, ml used in titration to neutralize every aspirin trial.
Raw Data Collection:
Quantitative Data:
Aspirin A: Trial | Aspirin Tablet | Uncertainty (ml) | Burette Reading NaOH(ml) | Resulting | Uncertainty (ml) | | (Grams) | | Initial (ml) | Uncertainty(ml) | Final (ml) | Uncertainty(ml) | NaOH (ml) | | 1 | 0.598 | -+0.001gr | 13.50 | -+0.05ml | 40.60 | -+0.05ml | 27.10 | -+0.10ml | 2 | 0.603 | -+0.001gr | 11.90 | -+0.05ml | 40.80 | -+0.05ml | 28.90 | -+0.10ml | 3 | 0.599 | -+0.001gr | 9.50 | -+0.05ml | 37.40 | -+0.05ml | 27.90 | -+0.10ml | Average: | 0.600 | -+0.001gr | 11.63 | -+0.05ml | 39.60 | -+0.05ml | 27.97