| Centrifuge: used to isolate the solid from the solution | . Focus Questions: When acidified water is not used in the zinc and iodine synthesis, zinc hydroxide is formed. How can it be identified based on the amphoteric nature. When zinc and iodine react without the presence of acetic acid in the water, zinc hydroxide forms. This is evident because the substance tested positive for both the acid test and the base test for zinc hydroxide.
Transform the data into the a graph- Cumulative Mass of zinc in grams (y-axis) vs cumulative displaced water in mLs (x-axis) Confidence Report- My partner and I are very confident in our results gathered during is lab. The density of the zinc found during the experiment was 7.0 g/mL. This value is very close to the value stated in the CRC Handbook of Chemistry, which is 7.14 g/mL. As for our materials, the beakers and graduated cylinders where cleaned thoroughly to prevent contamination in our observations of zinc and iodine. The test-tubes used for the solubility tests of zinc and iodine were washed and dried as well.
This helped avoid future error of using the wrong chemicals in our experiment. In our group, we split up the tasks. I did solubility while Salowa observed the mass of zinc versus the displacement of water. Yet we both made sure we did double checks. When observing the solubility I asked Salowa to take a second glance at the iodine or zinc in the test tube, just incase I missed something.
Lab Report- Grand Central Equation Introduction In this experiment, we created Zinc Iodide yet again. However, this time we did it through different means which caused a different kind of reaction. Better said, in this lab we learned that reactions can take multiple steps to go into completion. We also analyzed which was the more efficient way to generate Zinc Iodide. Focus Question Should chemists prepare Zinc Iodide, from its elements or from a Double Replacement Reaction between Barium Iodide and Zinc Sulfate?
What are the identities of the substances found after electrolysis and heating? The identities of the substances found were Iodine, Iodide ion (I-), Triodide ion(I3-), Zinc metal and Zinc ion(Zn2+) Post Lab questions: 1. What did this experiment convincingly show about the composition of the white solid? I put that the experiment showed us the white substance was comprised of Zinc ions and iodide ions, and that the two ions and be separated back into their respective elements 2. During the electrolysis, a gray solid formed on the negative wire of the battery and the dark red solution formed at the positive wire of the batter.
Appearance Iodine: silver sphere solid Zinc Shot: Round flat silver Zinc Granular: pencil shaving like silver solid Potassium iodide: white thick powder Focus Question: How well does the appearance and solubility of iodine and zinc respectively compare with information presented in the CRC Handbook of Chemistry and Physics? The appearance and solubility of iodine and zinc that we observed n the lab are very similar to the information presented in the CRC handbook of chemistry and physics. The iodine pieces we observed in lab were insoluble in water, and soluble in potassium iodide (very soluble), mineral oil (slightly soluble), and alcohol (slightly soluble). This consigns with what the CSC handbook stated that’s potassium iodide,
Before beginning the actual experiment, we used the mixing tables that were given to us to set up the test tubes with the appropriate substances. We followed the same procedure for each experiment variable (1-5). We then “rid the cell of toxic hydrogen peroxide (H2O2) so the cell would not get damaged,” as
Through our identification tests, we identified the gray solid to be zinc granules, the colored solution to be zinc ion and iodine-iodide-triiodide ion in water and the white solid to be solid zinc iodide. These identifications compared well with two other groups data. Ismat Zerin and Savita’s group also identified these substances to also be zinc granule, zinc ion and iodine-iodide-triiodide ion in water, and zinc iodide. Even though our conclusion was the same, our identification results did differ to some extent. For the identification test for the gray solid, we all concluded that this substance showed negative results for every chemical tested except for the zinc metal.
This experiment served as a test of our individual laboratory skills in carrying out several chemical transformations involving copper. To recognize that change of state, change in color, formation of a precipitate, or the evolution of heat are associated with a chemical change; to study reactions of copper. The experiment was successful in that the percent yield was reasonable, however we were not able to recover our copper sample with maximum efficiency ( we ended up with an excessive amount ). INTRODUCTION The purpose of the experiment is to cycle solid copper through a series of five reactions. At different stages of the cycle, copper was present in different forms.
This was so that the mussel samples would not go bad due to heat or harsh solvents. They were extracted with a mild solvent, and then concentrated by evaporation. The team found that the vapor was not toxic, but the residue after was. Other extractions were done to see how the residue separated when added with other mixtures of nonpolar solvents. In the toxic mussels, the visible light absorption spectrum revealed a pattern that was characteristic of phytoplankton pigments.