Separation of a Mixture of Solids

Separation of a Mixture of Solids My Flow Chart First remove iron filings with magnet since this is the only substance in the mixture that it is magnetic and will be attracted to a magnet. Second remove the sand by adding the mixture to hot water, which the other two substances are soluble. Third remove the benzoic acid since this is less soluble in cold than salt by cooling the mixture in the heated water. This will then leave the table salt behind in the water as the last substance. Observations Data Table 1: Experiment Data| Grams (g)| Percent of Mixture (%)| Initial Mixture| 6. 5| 100| Iron Filings| 1. 8| 27. 69| Sand| 1. 7| 26. 15| Table Salt| 1. 9| 29. 23| Benzoic Acid| 0. 8| 12. 31| Combined Total| 6. 2| 95. 38| Questions A. How did your proposed procedures or flow charts at the beginning of this experiment compare to the actual procedures of this lab exercise? My proposed flow chart was very close to that of the actual lab exercise. The only step that I did not include was letting the water evaporate to find isolate the table salt.
I suppose I was thinking that it would be estimated by process of elimination. However, I can now that this would not accurately show that true weight and is therefore not scientific. B. Discuss potential advantages or disadvantages of your proposed procedure compared to the one actually used. The disadvantage of my flow chart would be that although the end numbers would be closer to the original mass of the mixture, it would not accurately represent the correct percentages and would not account correctly show the rror that occurred during the process. C. How would you explain a sand recovery percentage that is higher than the original sand percentage? I would explain a sand recovery percentage that is higher than the original sand percentage from water that could still be let in the sand if it has not been given the proper time to fully dry. However, the a small amount of table salt and benzoic acid particle were also left behind in the small amount of water that needed to be dried out of the sand and could account for the higher percentage.
D. What were potential sources of error in this experiment? I think that the largest potential for error is in the transfer and handling of the substances. Small particles were left behind in the original weighing dish, graduated cylinder and cup that were not able to be transferred. Human error, like spilling small amount of the mixture in transfer, and mechanical error, like a miscalculated calibration of the scale, could also be sources of error.