Alum Lab Conclusion

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Alum Lab Conclusion
The purpose of this laboratory was to use two different techniques to attempt to identify the melting point and the mole ratio of hydrated water to anhydrous aluminum, potassium, and sulfate of AlKSO4. The hypotheses were: if the alum was put in a capillary tube the melting point of alum will be able to be determined; and the water of hydration in alum crystals will be possible to determine if the alum is heated with a Bunsen burner. Results:

Part 1: Data Table
| Trial 1| Trial 2|
Measured Melting Point| 93 (degrees C)| 91.5 (degrees C)| Literature Melting Point| 92.5 (degrees C) | 92.5 (degrees C) |

Part 2: Data Table
Mass of crucible and cover | 23.573 g|
Mass of crucible, cover, and alum crystals| 25.574 g|
Mass of alum crystals| 2.001 g|
Mass if crucible, cover, and alum after heating | 24.6578| Mass of water driven off| .916 g|
Mass if anhydrous alum| 1.085 g|
Moles H2O | .051 mol|
Moles AlK(SO4)2| .0042 mol|
Mole ratio, moles water to moles alum| 12/1|

Every compound has its own unique sets of chemical properties. Alum crystals are of great purity and are easily prepared. Because of their purity, they are often used in dyeing cloth, where the alum acts as a source of Al+3 ions which are not contaminated. These properties can be determined experimentally and in this experiment as mentioned above, a few properties of alum were being determined. The first test was to identify the melting point of the alum and compare it to the published value that already exists. The melting point of a substance is a property that indicates at what temperature it goes through a state change of solid to liquid. In order to do this, the alum was placed in a water bath and heated. In the second part of the experiment, the alum was analyzed for water of hydration. When an ionic compound is prepared in aqueous solution and isolated by crystallization, water molecules are incorporated into the...
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