The average concentration of the solution is 0.0829 mol/L.
As one began with an expected concentration of 0.1053 M (given that one began with a solution with 0.1053 moles of NaOH, and 1 L of deionized water), given the resulting average experimental concentration of 0.0829 mol/L, this indicates significant error within the experiment.
Calculation of error:
Trial 1: 31.11%
Trial 2: 8.52%
Trial 3: 24.25%
Possible sources of error include:
- Failure to properly measure the mass of the solutes (thus reducing the accuracy of all further calculations).
- Failure to flush all of the deionized water from the titrator.
- Failure to titrate beyond the equivalence point (making determining the point at which the two solutes had completely reacted impossible).
- Failure to keep the solution mixed while titrating, introducing the possibility that the solution may not completely react in areas, and the possibility of inaccurate measurement.
- Failure to properly handle the solutions, introducing the likelihood of contamination (NaOH can react with carbon dioxide in the air), thus disrupting measurements.
- Failure to properly measure the mass of the NaOH, or KHP (disrupting all further calculations).
- Human error is always in effect, given that the laboratory does not function under ideal conditions. As such, there is always the possibility of inaccuracies with measurement, perception of measurement, inaccuracies of equipment, and other such errors. (However, this is not likely to be the sole cause of the inaccuracies within this experiment, though it may contribute to it.)
Possible improvements that one could make to the experiment include using a more accurate pH probe, using more accurate balances, using a more accurate titrator (the syringe could be made more accurate), ensuring that lab partners read the experiment beforehand (increasing familiarity with the procedure, and minimizing human error), preparing the solutions in an atmosphere that lacks carbon dioxide (to avoid reaction of the NaOH solution), and repeating the experiment multiple times (to minimize the impact of an anomalous result).