Hydration Lab Essay

The purpose of this lab is to determine the weewee of hydration of a step up (CuSO4) by heating it and hence find its chemical formula. It was determined that the compound contained 4 moles of H2O for every 1 mole of CuSO4, hence had the formula CuSO4 4H2O and sloven II Sulfate Tetrahydrate. However, the literature value was 5 moles of oxygen for every 1 mole of CuSO4 (Copper II Sulfate Pentahydrate CuSO4 5H2O).As calculated above in Data Processing, this convey that the percentage deviation from the literature value was 20%. This is significantly less(prenominal) than the percentage suspense, which was 37%. This should indicate that the random error was higher than doctrinal error, because period there was a high level of uncertainty, the literature value still falls within that value, meaning that the measurements were close enough.In reality, though, this high level of uncertainty says more about the inaccuracy of the measuring equipment than it does about the amount of systematic error. For example, it is possible that simply non all of the water was removed from the compound. On the contrary, the lab surgical procedure instructed to continue trials of heating the compound and weighing it until the mass values were within 0.05g of each other. Those in this lab were only 0.01g apart a difference which would not have make believeed the outcome of the lab. This means it is unlikely that there was a significant amount of water remaining in the compound.Evaluation of ProcedureIt cannot aboveboard be said that this lab was executed successfully. This is for two main reasons1. the false result2. the high degree of uncertaintyThe first of these is surely the most Copernican this lab did not achieve the desired result. While the compound had a water of hydration of 5, the lab results said that this value should be 4. In some circumstances, such error could be tolerated indeed, 20% is not terrible. However, the very purpose of the lab was to determi ne the compound, and this goal was not achieved.The second point is how uncertain the data genuinely was. Based on the percentage of uncertainty, the water of hydration could have been anywhere from 2.5 to 5.5. This does contain the literature value, but has a range of more than half of that value (3/5). If the water of hydration could nearly have been 2 or 6, does this lab truly reveal anything? It gives a vague estimate of how much water there is, but picayune more.Much of the uncertainty was caused by an imprecise scale used in the initial measurements. Only after the procedure requested precision to two decimal places was a more precise scale used, and the initial measurements were still only accurate to 0.1g. Also, if the mass of compound used had been higher, the percentage error would have been less simply because it would be a smaller portion of the measured value.Improving the InvestigationThis lab did not meet its goal, hence definitely should be improved. The simplest diversify that could be made is to use the more precise scale from the beginning of the experiment. This would reduce the percentage error down to 6.7%, a much more conjectural value. This, however, does not solve the problem of the inaccurate value determined, because it is unlikely that this scale would have been any more accurate, despite being more precise.It is hard to pinpoint, therefore, only where the experiment went wrong, as it seems that the scales were not at fault but that a sufficient amount of water had been removed. There was certainly some kind of systematic error.One way that this error might be reduced, even without understanding its source, is to increase the amount of substance measured. Because the lab is about obtaining a ratio, this would not affect the result at all except hopefully to decrease the effect of any systematic error. This would, however, have the disadvantage of making the lab take longer, and locomote might need to be added to ensure that a ll of the compound has a chance to dehydrate.