ScottJessicaKatheren

Katheren Pomera, Scott Brevda, Jessica Heras Class 1101 Chemistry **__ Chemistry Lab #16 Method Section __** First, procure a scale, make sure the balance is set to grams unit, and then take one of the empty crucibles, weigh a cook crucible and record the results in the original. Next, with the same crucible, use a scoop to add a small amount of one of the mystery hydrates, enough to completely cover the bottom of the previously empty crucible. The same process is applied to the other crucible with a different hydrate. After that, weigh both crucibles with the different hydrate then record the results. Hydrates have different labels on the lab paper so that the observations and results will not mix up. After placing the hydrates into the crucible, observe the hydrate carefully- the state of matter, the texture, etc. Following, the mass of each hydrate is calculated. To find the mass of each hydrate, the mass of the empty crucible is subtracted from the mass of the crucible with the hydrate. The result is the mass of the mystery hydrate; the same method goes for the other sample. Once done with observations and calculations, either one of the crucible with hydrate are placed above the burner on the crucible stand. The hydrate is heated for 4-5 minutes and while it is being heated, the hydrate is being observed from a far so that no accident will happen. After the hydrate is heated for 4-5 minutes, the burner is turned off. The crucible was carefully removed from the heat using the crucible tong for safety. As soon as the crucible cooled off, the anhydrate was observed and observations were written down on the lab sheet. The crucible was then placed on the balance, and the mass of the cooled crucible and the anhydrate was recorded on the paper. The mass of that same crucible when it was empty was subtracted from the mass of the cooled crucible and the anhydrate, and the result was the mass of the anhydrate itself. The same routine was used for the other sample. Once that process was done, it was time to find out the mass of the water that was lost. Subtraction was once again used in this computation. The mass of the anhydrate was subtracted from the mass of the hydrate and the product was the mass of the water and then the result was recorded on the lab sheet. Lastly, the percent mass of water in the hydrated was computed. This was done by dividing the mass of water lost by the mass of the unknown hydrate. The result was then converted into a percent by multiplying the result by 100. The percent mass of water in the hydrate was written down on the lap paper. Then base on the results and reports, the mystery hydrate was then identified by comparing the mystery hydrate’s percent mass of water to the percent mass of water of the known hydrate, if the percentage between the hydrates was close, it was then concluded that it must be the same hydrate.