Synthesis and Decomposition of Zinc Iodide
Experiment Performed on
In this experiment, the elements Zinc and Iodine were combined in their solid form with acetic acid and water. This solution was decanted then heated slowly to complete the synthesis process. Then result Zinc Iodide, was shown by pouring the remains into an evaporating dish and tested with electrolysis. This experiment displays the Law of Conservation of Mass. Introduction
To obtain zinc iodide a reaction must occur between zinc and iodide, represented by: Zn(s)+I2(s)->ZnI2(s).
This reaction will not occur with just the elements because they cannot get close enough to react with each other. Therefore a weak acid is made by mixing acetic acid and water then added to the zinc and iodide allowing them to move close enough to react with each other. Once this weak acid is added the reaction takes a just a moment to occur. While forming ZnI2(aq) a secondary reaction will also occur represented by: I(s)+I2(s)->I3(aq).
Which will react with zinc to form Zn( I3)2 or zinc tri-iodide, displaying the red wine color that is observed, which is represented by:
Zn(s)+I3(s)->Zn(I3)2(aq). This is an ionic compound and reacts with the excess Zinc to form the Zinc Iodide. The secondary reaction has no effect on the booking. However, the solution ZnI2 could have continued to react in a double replacement reaction with the water had the acetic acid not been added to it. This would reduce the amount of result formed though. This could be viewed as violating the Law of Conservation of Mass. However this reaction is easily prevented with the addition of the acetic acid which is removed with heating once necessary and does not react with any of the substances. Completing this reaction a solution and a solid were created. The Zn(s) and I(s) were separated from the zinc iodide and acetic acid solution, by decanting the liquid. The acid and water were removed by slowly...
Please join StudyMode to read the full document