Chemical Compound Of Alum And Souric Acid
The purpose of the first part of the experiment was to produce a chemical compound which was the alum crystals by using aluminum, potassium hydroxide and sulfuric acid. After the compound was present, the purpose of the second part of the experiment was to make sure that the compound that was formed in the first half of the experiment was actually alum. Some of the experimental techniques that were used in this experiment was filtration using the Büchner funnel vacuum filtration, recrystallization using an ice bath, melting point using the Mel-temp equipment and water of hydration using heat to dehydrate the compound. For the experiment, the theoretical yield appeared to be 18.90g of alum and the actual yield was 12.198g of alum, which resulted
in getting a percent yield of 64.54%. When calculating the melting point the range of 98.8˚C- 102.5˚C was found which was close to the literature value of 100˚C. The salt to water ratio in the crystals was determined and came out to be 1:4 or KAI(SO4 )2• 4H2O. Using this ratio the percent error was calculated and came to be -0.650%. During the experiment, after pouring the acid into the substance, cloudiness in the substance occurred. This helped to determine when the substance was able to be taken off the hotplate to cool which was when the substance became clear. Another important change notice was during the recrystallization process which turned the liquid into a slush as it got colder. At the end of the experiment what was left was a solid substance. Throughout the experiment some sources of error occurred through systematic errors and impurities. The hotplate was not hot enough and the ice bad wasn't cold enough. Also the cooling and heating process wasn't long enough which concluded the % error to be negative. Impurities like iron could have been in the aluminum result in inaccurate calculations.
in getting a percent yield of 64.54%. When calculating the melting point the range of 98.8˚C- 102.5˚C was found which was close to the literature value of 100˚C. The salt to water ratio in the crystals was determined and came out to be 1:4 or KAI(SO4 )2• 4H2O. Using this ratio the percent error was calculated and came to be -0.650%. During the experiment, after pouring the acid into the substance, cloudiness in the substance occurred. This helped to determine when the substance was able to be taken off the hotplate to cool which was when the substance became clear. Another important change notice was during the recrystallization process which turned the liquid into a slush as it got colder. At the end of the experiment what was left was a solid substance. Throughout the experiment some sources of error occurred through systematic errors and impurities. The hotplate was not hot enough and the ice bad wasn't cold enough. Also the cooling and heating process wasn't long enough which concluded the % error to be negative. Impurities like iron could have been in the aluminum result in inaccurate calculations.