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After viewing our percent yields for Zinc Iodide (which were around 100%), we believe this lab was conducted under the best of conditions and produced more than accurate results. In performing the experiment, the measurements for Zinc Sulfate and Barium Iodide did not deviate from the standard to be measured by more than 0.03g (as was indicated for precision in the lab manual). Each time we went through the centrifuge process, the same centrifuge machine was used. To make sure our boiling tube did not contain any remnants of zinc iodide from previous experiments to mess with our end results and measurements, we washed it out twice with tube cleaners and soap, and then dried it and placed in the two boiling chips. After the centrifuge process, we made sure to collect all the aqueous zinc iodide to the boiling tube by using a pipet to gather all the liquid. For this double replacement reaction, all the reactants used formed complete products; there was no excess anything (like when reacting Zinc and Iodine, Zinc Iodide and excess Zinc was produced). Also, while heating our Zinc Iodide for this lab, near the end we made sure none of the product spilled out of the tube. To boost confidence, my partner I and did the experiment each separately and repeated it two times. In comparing our results with Mona and Belle, their centrifuged product also produced a white precipitate and clean liquid and their percent yields were also around 100%. During the actual experiment, we also compared out physical products with Mona and Belle’s to make sure we created what was supposed to be created. After realizing that our percent yields and most of the other group member’s percent yields were over 100%, we took into consideration how that could have been, reactions should produce at most only 100% product. Even though our scales now measure to 2 decimal points, we don’t know how accurately we measured our compounds, and because our reactants were anhydrous, after measuring it, the moisture may have added to some of it. The humidity in the room was high the day this lab was conducted and also, it was raining outside which further added to the moisture in the air which seeped into our reactions. This may have been the reason why our results were raised up in numbers. After physically inspecting our Zinc Iodide made in this lab, we saw that its color was not as pure white as the one created when Zinc and Iodine are directly reacted. The color was a little more yellow, but then again the commercial zinc iodide provided in pervious experiments was also a little yellow. This is because factories in where the commercial product is made could be contaminated as well, which means our product may have been also. This may be because the zinc iodide produced in this experiment was not as pure as the ones created in previous labs, with barium and sulfate being in the reaction as well; it may have skewed with the end results of our zinc iodide. Another very important thing to note was that Renat had certain issues with his yields. After doing the experiment once, he proceeded upon doing the experiment once more. This time, he attained an impossible percent yield which was largely contributed to external factors such as moisture in the air as well as time constraints and centrifuging problems. However, pooling in his other trial as well comparing it to my trial and the trials of Mona and Belle, we concluded that we attained a reasonable and accurate percent yield. The important thing to note about this experiment was that it was repeated more than once and we compared it to other groups with similar precision. Human error and other external factors could have contributed to the percent yields.