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Methods Section:

A cool empty crucible was weighed on a automated balance to determine its mass. Its mass was recorded. 0.9 grams of unknown hydrate#1 was placed in the crucible. The crucible containing the unknown hydrate was then placed on the automated balance once again. The crucible containing the unknown hydrate was then removed from the scale, and a series of observations were then made of the unknown hydrate and recorded. In order to carry out the process of evaporation that was necessary to remove the water from the hydrate, the crucible was then placed on a crucible stand that was positioned for stability on a ring stand above a bun sen burner. The gas was then turned on, and the burner was lit using a striker. The flame was adjusted so that the blue curve was visible just under the crucible, allowing for maximum heat to reach the crucible. The hydrate was heated until no visible signs of water vapor remained. This was determined by observing the hydrate until all traces of the blue hue was gone from the hydrate. The gas was then shut off, which had turned off the flame. The crucible was then carefully removed from the ring stand using crucible tongs, and placed on the counter to be cooled. While this crucible containing the new an hydrate cooled for approximately ten minutes to assure no bodily harm occurred to any group members, the same steps were repeated for a crucible containing hydrate#3. When no signs of water vapor were evident, the crucible containing this new an hydrate substance was also removed from the ring stand using crucible tongs and placed on the counter to cool. This was determined by observing the hydrate until a green flame ceased to be emitted. While this new anhydrous substance cooled, observations were made to assess the changes that had resulted after evaporation. After observations were made, the crucible was returned to automated balance and its mass was recorded of water were calculated to have been lost during evaporation. Having these figures, the percent composition equation was applied and the percent mass water in the hydrate was determined to be 33.3%. The identity of the unknown hydrate#1 was determined to be copper (II) penta hydrate, whose percent composition of water is 36%. Having determined the identity of the first hydrate, the identity of hydrate#3 was then determined. These same steps were repeated with the crucible containing the anhydrous substance which was previously hydrate#3, except that the masses and calculations corresponding to this unknown hydrate were used. The identity of this unknown hydrate was concluded as Magnesium Sulfate Hepta hydrate.