Data for the Synthesis of Znl2 Mass of empty test tube Mass

Data for the Synthesis of Znl2 Mass of empty test tube: Mass of test tube containing zinc Mass of zinc Mass of test tube containing zinc and iodine Mass of iodine: 1.a. 1. c. 3. b. 32.005 4. Observation of reaction (write your observations in the space below) 414.003 6. Mass of test tube with boiling chip: Mass of test tube with boiling chip and recovered Znl Mass of recovered Zr12: a. 4420 6. f. 4.40-44.603 7. Mass of test tube with unreacted zinc: 5)-( )-653824 Mass of unreacted zinc: 0-34 474 6.247 Analysis of Znl2 I. Theoretical and Percentage Yield A. Calculate the moles of l2 consumed in the reaction (Hint: All iodine is taken to be consumed): 253.8 fnol . Based on the number of moles of 12 consumed, what is the theoretical yield of Znl,? Zla=(153 &/n.) + (65.38 Irol): 319.18.3/mo moles)(319.18 Formula mass

Solution

II-A)-In this experiment, zinc iodide was produced by the reaction of excess zinc and iodine. The empirical formula of zinc iodide was obtained through mole ratio by usingthe mass of iodine and the mass of consumed zinc, which was calculated by subtracting the intial amount of zinc by the mass of dry zinc. Thus, the final formula came out to be ZnI2. Also, the Law of Conservation of Mass was validated by the comparison of the mass of the actual product, and the mass of zinc consumed combined with themass of iodine. Although not perfect, the two values were relatively close to each other, confirming this law. Finally, chemical reversibility was proven through the electrochemical decomposition of the zinc iodide in solution.

In observing this reaction ,the appearance of Zn precipitate at one electrode and I2 in solution of a yellowish color atthe other electrode showed the decomposition of zinc iodide. Moreover, the electrode with the zinc precipitate would be the negative end, for zinc in solution has a positive charge, while the electrode with iodine would be the positive end, since iodine in solutionhas a negative charge.