Identification, Properties, and Synthesis of an Unknown Ionic Compound (Magnesium Chloride) Kaelyn O’Neill Chemistry 1010 Laboratory, Section 03 Instructor: Khushi Patel October 12, 2014 My signature indicates that this document represents my own work. Outside of shared data, the information, thoughts, and ideas are my own, except as indicated in the references. I have submitted an electronic copy through Blackboard to be scanned by TurnItIn.com. In addition, I have not given aid to another student on this assignment. Discussion and Scientific Explanation: Our team was employed by the Environmental Protection Agency to discover what our unknown compound was, and the physical and chemical properties of the compound. …show more content…
We first tested for the chloride anion using the silver nitrate test. 1 mL of our unknown compound was mixed with 1 mL of 6 M HNO3 and 1 mL of AgNO3 solution. A white precipitate was formed, indicating the presence of the chloride ion. (This precipitate indicated a reaction and the silver nitrate test states that if a reaction occurs, and a solid is formed than the chloride ion must be present.) But this test also gives positive results for the sulfate ion, so we also had to perform the barium chloride test. 1 mL of our unknown compound was mixed with 1 mL of 6 M HCl and 1 mL of BaCl2 solution. There was no formation of a precipitate whatsoever, indicating that there was no sulfate ion present. (The absence of a precipitate indicated no reaction, and the barium chloride only indicated the presence of a sulfate ion with the formation of a solid). Through this we were able to conclude that the anion in our compound must be chloride. These results are indicated in Table 3. Because we knew that the chloride ion was present, this narrowed our compound down to a possibility of five compounds, including NaCl, KCl, CaCl2, MgCl2, and …show more content…
We tried to dissolve the unknown compound and NaCl, KCl, CaCl2, MgCl2, and NH4Cl in HCl, toluene, and acetone, and all sets of results were inconclusive because all the compounds were insoluble in both solutions. These results are indicated in Table2. This told us that the compound was not an organic base or nonpolar (organic), just like all the other known compounds, confirming that our compound could be an ionic compound. This is because if a compound dissolves in 1 M HCl, it is probably an organic base, if a solution dissolves in toluene it is nonpolar (organic), and if it dissolves in acetone it is polar or nonpolar (probably not ionic) (Cooper). The inability of the compound to dissolve in the acetone gave us the greatest indication that the compound was probably ionic. The major problem with this test was that we were not allowed to use water, which would confirm that our compound was ionic if it was soluble. We could only eliminate other possibilities, but this data was not significant because we were already given that it was an ionic compound, yet it agreed with our research that MgCl2 was ionic, just like our