The aim of this experiment was to investigate which technique – out of gravimetric analysis and colourimetry – was the most appropriate and accurate method to practice when calculating the percentage yield of a reaction.
When examining the data obtained from the investigation, there was evident that there were some trends in the results. For the three graphs showcasing the results for gravimetric analysis in task one and task two, there was no general pattern. This was due to the fact that in Graph 1, the actual yield was a portion larger than the theoretical yield, while in Graph 3, the opposite results were obtained and in Graph 4, the actual yield was significantly higher than the theoretical yield. Nonetheless, the outcome of no general …show more content…
While it may take time to prepare the standard solutions of known concentration to develop the calibration curve for the spectrophotometer before testing a filtrate, the equations involved in determining the amount of a compound necessary for preparing solutions of specific volume and concentration are simple and do not take a large amount of time to complete. Additionally, when choosing reactants for a reaction before using colourmetirc analysis, one does not need to consult the table of solubility rules to see whether or not a precipitate will form. As evident from using gravimetric analysis in the second task, choosing a compound with low insolubility proves very difficult to filter and separate from the filtrate, therefore, resulting in needing to filter the precipitate more than once and still ending up with a low percentage yield and high error calculation. However, the contamination of a precipitate does not significantly alter the results for colourimetic analysis, as evident from the absorbance and concentration calculated for colourimetry in task two. Additionally, when using gravimetric analysis for larger volumes of reactants, the precipitate may be prone to become significantly …show more content…
As evident from the comment for the first task in the observations, the filter paper had a blue ring approximately one centimeter in width around its perimeter, prompting a presence of contamination. As the filtrate was also blue in colour, this signaled that it might not have completely filtered out of the funnel. Nonetheless, this idea of contamination could explain why the actual yield of the precipitate – being 0.68g – was higher than its theoretical yield of 0.61g, with the contamination adding extra hundredth-grams to the overall weight. Likewise as to what happened in the first task when using gravimetric analysis, a blue ring again formed around the perimeter of the filter paper in the second attempt of gravimetric analysis in task two. With the actual yield attained from the second attempt being 0.39g heavier than its theoretical yield, this contamination could have assisted the precipitate being a larger weight. Further strengthening this theory is the fact that the volumes of the reactants were increased. With a filtrate of 40mL rather than 20mL like in the previous two gravimetric analysis experiments, there was an even larger chance of significant contamination; therefore, explaining the fact why the yield for this analysis was the heaviest out of the three gravimetric
When examining the data obtained from the investigation, there was evident that there were some trends in the results. For the three graphs showcasing the results for gravimetric analysis in task one and task two, there was no general pattern. This was due to the fact that in Graph 1, the actual yield was a portion larger than the theoretical yield, while in Graph 3, the opposite results were obtained and in Graph 4, the actual yield was significantly higher than the theoretical yield. Nonetheless, the outcome of no general …show more content…
While it may take time to prepare the standard solutions of known concentration to develop the calibration curve for the spectrophotometer before testing a filtrate, the equations involved in determining the amount of a compound necessary for preparing solutions of specific volume and concentration are simple and do not take a large amount of time to complete. Additionally, when choosing reactants for a reaction before using colourmetirc analysis, one does not need to consult the table of solubility rules to see whether or not a precipitate will form. As evident from using gravimetric analysis in the second task, choosing a compound with low insolubility proves very difficult to filter and separate from the filtrate, therefore, resulting in needing to filter the precipitate more than once and still ending up with a low percentage yield and high error calculation. However, the contamination of a precipitate does not significantly alter the results for colourimetic analysis, as evident from the absorbance and concentration calculated for colourimetry in task two. Additionally, when using gravimetric analysis for larger volumes of reactants, the precipitate may be prone to become significantly …show more content…
As evident from the comment for the first task in the observations, the filter paper had a blue ring approximately one centimeter in width around its perimeter, prompting a presence of contamination. As the filtrate was also blue in colour, this signaled that it might not have completely filtered out of the funnel. Nonetheless, this idea of contamination could explain why the actual yield of the precipitate – being 0.68g – was higher than its theoretical yield of 0.61g, with the contamination adding extra hundredth-grams to the overall weight. Likewise as to what happened in the first task when using gravimetric analysis, a blue ring again formed around the perimeter of the filter paper in the second attempt of gravimetric analysis in task two. With the actual yield attained from the second attempt being 0.39g heavier than its theoretical yield, this contamination could have assisted the precipitate being a larger weight. Further strengthening this theory is the fact that the volumes of the reactants were increased. With a filtrate of 40mL rather than 20mL like in the previous two gravimetric analysis experiments, there was an even larger chance of significant contamination; therefore, explaining the fact why the yield for this analysis was the heaviest out of the three gravimetric