Also a very pale purple tint formed. Acid test: Added 2 mL of 1M NaOH- no Physical change was observed. Base test: Added 2 mL of .17M Acetic acid- No physical change observed. Table: Zinc (g) | Iodine (g) | Deionized water (mL) | Weight of boiling tube (g) | 1M NaOH(mL) | .17M Acetic acid (mL) | 2 | 2.01 | 5 | 40.73 | 2 | 2 | 2. Answer to focus question: Since it is amphoteric, it will act as an acid if reacts with base and act as a base when reacts with acid.
Jessica Atanova CHEM 104 lab 03/10/14 SUBSTANCES Granular zinc- gray crystal like | Iodine crystals- dark, circular, rock-like | De-ionized water: used for standard Zinc Ion procedure. | Materials: Boiling tube: for products. | Small test tubes: used to centrifuge the solution and precipitate | Graduated cylinder: used for measurement of water | Stirring rod: used various times to stir samples and solutions. | Spatula: used to measure and transfer the substances. | Centrifuge: used to isolate the solid from the solution | .
An aqueous solution of ammonium sulfate is allowed to react with an aqueous solution of lead(II) nitrate. Identify the solid in the balanced equation. A) (NH4 )2 SO4 B) Pb(NO3 )2 C) PbSO4 D) NH4 NO3 E) There is no solid formed when the two solutions are mixed. ____ 11. An aqueous solution of sodium carbonate is reacted with an aqueous solution of calcium chloride.
Once the zinc was added slowly to the solution, a gas was released and the solution began to change colors. The colors that occurred were light blue to light grey, to a clear blue, back to a dark blue, then grey color. Once the stirring process ended, the solution was slightly blue and not colorless. There were solids in the bottom. The reaction that occurred with this step was displacement and metathesis in the form of gas formation.
Take sample of Zinc Iodide and dissolve in solution. Then, take the battery, with exposed wire tips attached, and place the tips into the solution. In about 1-2 minutes, there should be a red-brown color coming out of one of the wires, and a dark substance depositing on the other wire, these should iodine and zinc respectively. 2. What are the identities of the substances found after electrolysis and heating?
Measuring Cylinder (1) f. Beaker (1) Results Table: Name of Compound | Observe atomic admission | Calcium Chloride CaCl2 | The flames turned into an orangey color then gradually turned redish brown with a bit of orange. | Barium Chloride BcCl2 | The flames turned into yellowish color then it became whitish and brownish and eventually turning green. | Magnesium ChlorideMgCl2 | The metal salt bubbled when it hit the flames then its flames turned orange and yellow. And the substance that is left on the spatula turned into a glue like white mask. | Nickel ChlorideNiC12 | The substance was green originally but turned yellow after being exposed to the flames.
| Observations of Chemicals | Zinc Sulfate | Powder of a white solid | Barium Iodide | Powder of a white solid. | Deionized water | Liquid, transparent. | Trial # | BaI2 | ZnSO4 | Theoretical Yield of ZnI2 | Actual Yield | Percent Yield | 1 | .67g | .45g | .499820g | .52g | 104% | 2 | .67g | .45g | .499820g | .52g | 104% | 3 | .66g | .46g | .493117g | .48g | 97% | Calculations for Cost | Double Replacement | Synthesis | 0.48 grams of Zinc Sulfate - $0.02 | 1.00 gram Granular Zinc - $62.50 | 0.67grams of Barium Iodine Dihydrate - $0.886 | 2.00 gram Iodine - ($74.90 × 2) - $149.80 | 0.52 grams of Zinc Iodide - $0.906 | 1.00 gram zinc - $0.212 | 1000 grams of Zinc Iodide = $1,923.00 | 1000 grams of Zinc Ioidide = $212.30 | Focus Question Should chemists prepare Zinc Iodide, from its Elements or from a Double Replacement Reaction between Barium Iodide and Zinc Sulfate?
Observations: Quantitative & Qualitative Data Table Table 1: Solubility Qualitative data: Substances | Time (s) | Soluble or not? (Yes/No) | X | 42 | Yes | Y | 63 | Yes | Z | >180 | No | Table 2: Appearance of the substances while melting Substance X- White rocky powdery dots Qualitative data: Time (s) | Physical appearance of substance X | 10 | White powder dots | 26 | White powder dots | 44 | White powder dots | 55 | White powder dots | 65 | The color of the white powder dots changes to brown powder dots | 82 | Starts to melt a tiny bit | 107 | It stops melting, and there are still white powder left | 125 | Stays as white powder, no melting | 155 | White powder dots, nothing happens | 178 | White powder dots, no melting | 183 | White powder dots, nothing happens | 207 | A few of the tiny white dots starts to melt again | 230 | The white powder stops finally stay still | Table 3: Appearance of the substances while melting Substance Y- White crystal dots Qualitative data: Time (s) | Physical appearance of substance Y | 3 | White crystal dots | 20 | White crystal dots, no change | 40 | White crystal dots, no physical change
- signs of chemical change = changes the shape and color, creates a gas, distributes heat, Etc. - Chemical Change= Substance is formed into a completely new substance 2. Hypothesis: If the copper is being tested in these metals ( Copper, Magnesium and cupric chloride) then it would be the least reactive out of magnesium and zinc because it is the lowest among the three on the activity series. 3. Experimental Design: - Independent Variable: different types of metals: magnesium, zinc and Copper - Dependent Variable: amount of reactants observed for each metal - Control : The Air -Constants: The amount of chemical solutions, the time the metals were in the chemical solutions and size of each metal during the experiment 4.
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,