Ib Chemistry Analysis of Iron Tablets

969 WordsJun 9, 20124 Pages
DCP + CE: An Analysis of Iron Tablets |Pipette Solution |Iron (II) solution | |25 cm3 | |Burette Solution |Potassium Manganate (VII) |0.01 moldm-3 | | | |Trial |1 |2 |3 | | |Burette Readings |Final |11.35 |10.90 |10.95 |10.95 | | | |Initial |0.00 |0.00 |0.00 |0.00 | | |Volume Used…show more content…
As permanent colour change is subjective, the detection of the end point is inconsistent, resulting in an imprecise experiment. However, systematic errors affected the experiment the most. The most significant systematic error was reading off the amount of potassium manganate (VII) used in the titration from the burette. Due to the deep purple colour of the solution, it was very difficult to read the increments. For both the initial and final burette readings, readings might have been taken off the top of the meniscus, causing an overestimation of potassium manganate (VII) needed and thus, the experimental mass of FeSO4 in one tablet was larger than the manufacturer’s claim of 300mg in one tablet. Additionally, the dissolving method of the iron tablets was a major systematic error. Because we were just using a glass rod to crush and stir the iron tablets and because of the limited time spent on the procedure, the iron tablets may not have been completely dissolved in the water. Hence, there would be less Fe2+ ions in the iron solution and thus, less potassium manganate (VII) would be needed to reach the end point. Some Fe2+ ions might also have been lost on the filter paper or the beaker whilst transferring the solution, thus causing less potassium manganate to reach the end point and resulting in inaccurate measurements and calculations. Evaluation: As seen from the relatively small percentage error (1.49%) of my experimental result when compared to
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