1. In the fume hood, place 6 mL (5.6g. 0.056 mole) of cyclohexanol in a 400-mL b
ID: 1013154 • Letter: 1
Question
1. In the fume hood, place 6 mL (5.6g. 0.056 mole) of cyclohexanol in a 400-mL beaker. Place the beaker on a magnetic stirrer, add a stir bar, and begin moderate stirring. Clamp a thermometer and position in the beaker to monitor the temperature of the reaction. The stir bar should not be striking the thermometer. a) Add 100 mL of a commercial household bleach such as Clorox (5.25% NaOCl, 0.75 M) to a seperatory funnel. Add to that 4 mL of 17M acetic acid. Take care not to come in contact with the bleach/acid mixture. b) Begin adding the bleach mixture at such a rate to keep the in the range of 40-50°C (the oxidation reaction tempe reaction is stirring- decrease-the rate if the temperature begins to climb too high. The temperature can also be regulated by the rate of c) The reaction can require up to 20 minutes of stirring before the temperature cannot be held above 40°C. After all the bleach has been added the temperature will begin to fall. Continue stirring the mixture for an additional 25 min to complete the reaction. Stir the reaction mixture for a total of 45 minutes (even if the addition of the bleach required less than 20 minutes). d) e) At the end of the stirring period, if the solution is yellow to green in color then add small amounts of sodium bisulfite until colorless. This will reduce any free chlorine to chloride ion. f Add 10 mL of 6M NaOH to neutralize the acetic acio 2. Transfer the reaction mixture to a 250-mL round-bottomed flask, add a boiling chip, and set up an apparatus for simple distillation. Use a Bunsen burmer as the heat source, and a 125mL Erlenmeyer as the collection flask. a) Distillation under these conditions is a steam distillation in which the steam is generated intemally (in situ). Run the distillation until no more cyclohexanone comes over with the water, usually after 50mL of distillate is collected. about 5 grams of sodium chloride to the collection flask, and stir or swirl to dissolve the salt b) To decrease cyclohexanone's solubility in water, add CHEM 2425 Lab/Fall 2011 NLChemExplanation / Answer
For the oxidation of cyclohexanol by bleach
Limiting reactant
moles of cyclohexanol = 0.056 mol
moles of NaOCl = 0.75 M x 0.1 L = 0.075 mol
moles of acetic acid = 17 M x 0.004 L = 0.068 mol
1 mole of cyclohexanol reacts with 1 mole of HOCl formed by reaction of 1 mole of NaOCl with 1 mole of CH3COOH.
As number of moles of cyclohexanol is lowest, this is the limiting reactant.
Theoretical yield of product = 0.056 mol x 98.15 g/mol = 5.50 g
Properties of product : Product is a ketone with C=O stretch in IR region. Three sets of signal in NMR spectrum.
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.