The absorption spectrum is measured using a spectrophotometer and the data is graphed in Excel. The peak of the line is used to find Vmax of Fe2+. Vmax is used to find the moles of Fe2+ and ligand. The unknown n is a ratio of moles ligand divided by moles Fe2+. Results and Discussion For the first part of the experiment (Part A), five different 100 mL volumetric flasks were each filled with 1,2,3,4 and 5 mL of iron (II) solution.
Add 1 mL of deionized water to the small test tube containing the precipitate and mix it and centrifuge it for 60 seconds. Then, add the supernatant into the boiling test tube and repeat this step one more time with another 1 mL of deionized water. Acquire a pair of metal test tube holders and heat the boiling test tube to evaporate the water for 15 minutes. Let is cool after and weigh it. Then, calculate a percent yield of zinc iodide and write a balanced chemical equation and determine the limiting
Experiment 8 DETERMINATION OF % COMPOSITION OF PENNIES USING REDOX AND DOUBLE DISPLACEMENT (PRECIPITATION) REACTIONS Introduction: The main purpose of the lab is to determine the percent composition of pennies using oxidation reduction and double displacement reactions and titration techniques. The quantitative determination of zinc is conducted by precipitation followed by isolation and weighing of the Zn(OH)2 precipitate (gravimetric analysis). My expected results were that 97.5% of the penny would be zinc, and 2.5% would be copper. Experimental Procedure: 1. Obtain beaker filled with 250 mL of HCl and 5 pennies.
Materials and Methods Part 1 For the cation elimination test first 10 drops of potassium, iron (III), zinc (II), copper (II), and cobalt (II) were added to 5 centrifuge tubes and the color was recorded. Then for the metal hydroxide test, 6 M NaOH was added drop wise till a precipitate was formed. Each solution except potassium formed a precipitate, so then 10 additional drops of NaOH were added to the remaining solutions. Tubes were cleaned with distilled water and 6 M HCL. Next was the ammonia test 10 drops of each metal solution were added to new centrifuge tubes and 15 M NH4OH was added until the solution changed color or a precipitate was formed.
Part C: Density of Sodium Chloride (NaCl) Solution, a sample of NaCl was obtained and measured using a 100mL beaker and a 10mL pipet to determine the concentration of the solution. In order to obtain the appropriate result, a calibration graph and density measurement was used to determine the concentration of the sodium chloride solution. In conclusion, based on the water temperature of 21.8°C in part A’s graduated cylinder experiment obtained, it was determined that the average density was .0973g/mL with a percentage error of 2.5%. When graphed the measurement was equal to Y=0.988x. Part B: The graduated pipet’s average density at 22.3 °C was determined to be 0.9785g/mL with a percentage error of 1.89% shows the graduated pipet to be more accurate and precise.
Reactions Lab David Vaghari INSTRUCTOR: Dr. Chernovitz Monday, July 23, 2012 Oxygen Production Introduction In this lab, potassium chlorate will be decomposed producing oxygen gas and potassium chloride. The hypothesis is that the reaction will yield 3.916 grams of oxygen gas. Materials Test tube 10 grams potassium chlorate Bunsen burner Procedure Step 1. Obtain a test tube, place a 10 gm of potassium chlorate. Step 2.
Title: 1pt Stoichiometry Of A Precipitation Reaction 2. Procedure: 2pt (Write the procedure in your own words after you have read the lab manual) Put on goggles the weigh 1.0 of CaCl*2H2O and put it in 100ml beaker. Add 25 mil of water and stir. I will then use stoichmetry to figure out how much Na2CO3 I will need for a full reaction. I will weigh this and put it in a separate cup.
Abstract The focus of this experiment was to analyze the kinetics of a nucleophilic substitution. A mixture of 0.3622-M 1-bromopropane and 0.3622-M potassium hydroxide in an 90:10 ethanol/water solvent provided the reactants for a SN2 reaction to occur in a temperature controlled bath at 50.0˚C. The disappearing reactant was found by titrating timed aliquots during the reaction and then measuring the concentration of hydroxide. The k-value was found to be 0.0202 M-1Min-1. Using the linear form of the Arrhenius equation the activation energy was calculated to be 19.9 kcal/mol.
K12_1821161 $500 Answer from 3 Jan 9, 2014 1:03:23 PM Page 34. Blackboard Collaborate ?? K12_1821161 $100 Question from 4 Jan 9, 2014 1:03:23 PM Page 35. Blackboard Collaborate ?? K12_1821161 $100 Answer from 4 Jan 9, 2014 1:03:23 PM Page 36.