Name: Daniel Voskresenskiy Post-Lab Report Lab Name: 68th & Zinc - Lab #6 Course: CHEM106 LB SEC: 052 Date: March 18, 2013 Lab Partner: Justin Nus Observations of Reactants (Table 1) Chemical 0.17 M Acetic Acid Buffer 10 Unknown Zinc Compound Physical Appearance Aqueous; clear; colorless Aqueous; clear; colorless; not viscous Fine; Powdery; White; Solid Chemical Zinc Iodide (ZnI2) Calmagite NaEDTA Physical Appearance Solid; powder; fine; white Aqueous; brown/red; not viscous; opaque Fine; Powdery; White; Solid Procedure - Preparing a Solution of EDTA Before titration, a titrant must successfully be made - the substance that will react with zinc ion. Purpose: To find out how much zinc is a sample of zinc iodide we will react zinc
Zinc ion and Iodine-iodide-triodide ion in water: It was a liquid solution in a bottle, it was very dark orange-brown color. Solid Zinc Iodide: A very white powdery substance that had several clumps within it. It was also very dry in nature. Mass Table Substance Amount of Mass Measured for Actual Mass Granular Zinc 2.0 grams 1.9 grams Iodine Crystals 2.0 grams 2.1 grams Observation of Reaction Shown below and Included within the lab notes on pages 12 and on page 14. Placing Acetic Acid in Zinc and Iodine test tube After placing the Acetic Acid in a normally unreactive test tube containing Zinc and Iodine, the solution changed to a more orange and then to a more red-brown color.
Fill the burette with 0.005mol dm-3 potassium manganate(VII) solution. 6. Pour some of the thyme extract solution into a 250cm3 plastic beaker. 7. Using a measuring cylinder, add 50cm3 of 1.0mol dm-3 sulphuric(VI) acid to the thyme extract in the conical flask.
0.00512 * 500 = 2.56 c. 0.00806 * 319.9= 2.56 d. 0.00806 * 319.9 = 2.56 500 mL =0.5 L e. 0.0161 * 500 / 2 =2.56 4. Exercise 4: a. 0.250M; 250 mL 0.25 L (0.25) (0.25) = 0.0625 moles ZnI2 b. Prepare the solution by dissolving 19.95 grams of Zinc Iodide with 250 mL of water. c. Prepare the solution by dissolving 38.90 grams of ZnI2 with 500 mL of water.
| 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?
Results APPEARANCES OF MATERIALS USED Substance Physical Appearance Zinc Carbonate White; powderish Calcium Hydroxide White; powderish; like zinc carbonate 3 M HCL Clear liquid, resembles water 20 mesh granular zinc Grey, metallic, shiny 3% hydrogen peroxide Clear liquid; resembles water Manganese dioxide Very dark grey, black and powdery Copper sulfate Blue, crystalline in structure. Sky blue Zinc iodide Very dark purple, shiny and crystalline in structure 0.1 M acetic acid Clear liquid, resembles water Zinc oxide Very white powdery substance RAW RESULTS Data Specifided (Page 112 CRC handbook) Raw data Volume of Gas Collection Bottle (Average of 3 Trials) 14.04mL Mass of boiling tube (empty) 41.57g Mass of boiling tube with zinc carbonate 43.42g Mass of zinc carbonate 1.75g Volume of water in gas collection bottle after reaction 78.5mL Volume of gas product collected 185.2mL Mass of solid product with boiling tube after reaction 1.11g QUALITATIVE TEST RESULTS Group # Test Observation: Standard Positive/Negative Observation: Experimental Positive/Negative 1 H2 HCL + Zinc bubbling + flaming stick POP! + + flaming splint no POP - 2 CO2 Turned cloudy + Negated from experiment Negated from experiment 3 O2 MgO2 + Hydrogen Peroxide bubbling. Glow stick re-ignited + + wooden splint; glowing stick went out - 4 H2) Added 1 pea size CuSulfate + 1 drop of deionized water; blue, positive + Copper sulfate did not change color when put into wet filter paper - 5 Zn (OH)2 Zinc iodide + 3mL H2O Clear suspension + Visual inspection; cloudy. Acid test= solid + 3M Acetic acid cloudy + 6 ZnO ZnO + Heat yellow Zn Cooled White + ZnCO3 + heat yellow solid.
There will have some error. 2) A volatile liquid was allowed to evaporate in a 43.298 g flask that has a total volume of 252 ml. the temperature of the water bath was 100˚C at the atmospheric pressure of 776 torr. The mass of the flask and condensed vapor was 44.173 g. calculate the molar mass of the liquid. T = 273 + 100 = 373 V = 252 mL = 1 L / 1000 mL = 0.252 L P = 776 Torr R= 0.0821 mass of 44.173 - 43.298 g = 0.875g moles of gas = PV / RT = 776 x .252 / 62.363 x (273+100) =0.00841 moles molar mass = 0.875g / 0.00841 moles = 104.1 g/
Purpose: To investigate the physical and chemical properties of pure chemical substances. Observations and Experimental Data: Data Table 1: Solubility or Reaction Substance Name Color Odor Effect of Heat Cold H2O Hot H2O Litmus Test Dilute HCl Dilute NaOH Mg Silver odorless nothing bubbles bubbles No color change Bubble,fizz Slightly frothy cloudy No apparent change Cu Copper Odorless Turns darker black No apparent change No apparent change Lighter blue Holes in copper ball bubbles Dark spots on copper Zn Silver Odorless Liquid Solid Solid Lighter blue Bubbles fizzes No apparent change MgO white odorless Dark grey Cloudy Cloudy Lighter blue Fizzed bubbled Cloudy no bubbles CuCO3 green odorless pops Cloudy green h2o dissolved Turns dark green pops Blue-from pink Fizzed dissolved Turns blue Cu(NO3)2 blue odorless Melts boils Light green liquid Dissolved boils Blue-from pink Dissolved green liquid Blue bubbles NaCl white odorless crackesl Grain in h2o no bubbles Stays granular Lighter blue No apparent reaction bubbles Questions: A. Did you observe any chemical changes in this experiment? Yes. B.
White precipitate shows the presence of chloride (Cl-). Chloride anion equation: HCl(aq) + AgNO3 (aq) → HNO3 (aq) + AgCl(s). The nitrate anion test involves cooling a mixture containing 1 mL of test solution and 3mL 18M H2SO4. 2mL is poured down the inner test tube side and the presence of a brown ring shows nitrate (NO3-) to be present. The carbonate anion test mixes 1 mL of test solution and drops of 6M HCl.
Experiment 6: Physical & Chemical Properties Title and Identifiers: Heating of chemical properties 01/23/15 Purpose / Objective: • To investigate the chemical properties of pure chemical substances • To investigate the physical properties of pure chemical substances Procedural Outline: • Matches • Beaker, 100 mL, glass • Burner-fuel • Goggles-Safety • Stirring rod - Glass • Test Tube(5), 13 x 100 mm in Bubble Bag • Test-tube-clamp-holder • Test-tube-cleaning-brush • Well-Plate-24 • Well-Plate-96 • Litmus Paper, Blue • Litmus paper, Red • Copper (II) Carbonate in Vial, 1/2 Full • Copper (II) Nitrate Crystals in Vial • Copper Metal