• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

The preparation of cyclohexene from cyclohexanol

Extracts from this document...

Introduction

Title: The preparation of cyclohexene from cyclohexanol. Objectives: To prepare cyclohexene from cyclohexanol by an elimination method and to test for unsaturation in product. To introduce the method of purification for an organic liquid. Introduction: The acid-catalyzed dehydration of an alcohol is an important method for the preparation of an alkene. It is also an example of an elimination reaction, which proceeds by a first order mechanism via an intermediate carbocation. In this experiment, cyclohexanol is dehydrated to cyclohexene n the presence of concentrated phosphoric acid: Distillation is employed in this experiment to synthesize and purify cyclohexene. The principle of distillation as a separation method is based on the difference in boiling points of substances. The identity and purity of the product can be checked by infrared spectroscopy and gas chromatography. Apparatus: Conical flask x 3 250cm3 beaker x 1 50cm3 pear-shaped flask x 1 Spatula x 1 Filter funnel x 1 150? thermometer x 1 Oil bath x 1 Test tubes x 2 Hot plate x 1 Screw cap adaptor x 1 Condenser x 1 Ice bath x 1 Still head x 1 Aluminium foil x 1 piece Filter paper x 1 Dropper x 1 Stir bar x 1 ...read more.

Middle

As the result, almost none of water can dissolve in the cyclohexene so we can extract out the all-high purity synthesized cyclohexene. This is a separation called solvent extraction or salting out. Since the anhydrous sodium sulphate is a very good dehydrating agent, it is used to remove the water in the mixture with cyclohexene. As we add excess amount of anhydrous sodium sulphate into the mixture, the water can be absorbed by it and the remains are the cyclohexene and the rest of the anhydrous sodium sulphate solid. After filtration, the remained dehydrating agent can be filtered out so the dry organic cyclohexene can be obtaine 6. What is the percentage yield of cyclohexene in your experiment? The mass of the extracted dry cyclohexene = (Mass of conical flask with extracted dry cyclohexene - mass of dry empty conical flask) = 46.62 -42.16 = 4.46 g No. Of moles of extracted dry cyclohexene = Mass / molar mass = 4.46 / [(1.008) (10) + (12.01) (6)] = 0.0543 Density of cyclohexanol = Mass/volume So, the mass = Density x volume = 0.948 x 15 = 14.22g No of moles of used cyclohexanol = Mass / molar mass = 14.22/ [(12.01) ...read more.

Conclusion

6. It should be lubricating the glass joints evenly, using only a small amount of lubricant. 7. Clamp the apparatus at a suitable position, with the movable parts uppermost and firmly but not too tight. 8. Place the thermometer bulb in the correct position; adjust the position of the thermometer by unscrewing the adapter, sliding the thermometer through the ring and then retightening it. 9. Set up a water condenser by checking that the rubber tubing is of sufficient length, fitting the rubber tubing by lubricating with a little water, running water into the condenser from the lower end, and controlling the rate of flow of water so that the tubing is not disloged, and the rate is geared to the boiling point of the distillate. 10. Don't let the rubber too close to the heater. Otherwise, the rubber will be broken. 11. Check that the system is not a closed one, the joints are well fitted and the system is not tilted, 12. The anti-bumping granules are added when the liquid is cold. Conclusion: The cyclohexene can prepared from cyclohexanol by an elimination method and tested that it was unsaturated. Also the purification of the product by adding sodium chloride and anhydrous sodium sulphate is worked. 1 ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our AS and A Level Organic Chemistry section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related AS and A Level Organic Chemistry essays

  1. Determination of the formula of Hydrated Iron (II) Sulphate crystals

    x 100 =0.20% Total measurement percentage error =1.20% The total measurement percentage uncertainty for method 2 is considerably larger than it is for method one but it is still a very small percentage uncertainty. The greatest percentage uncertainty was caused by the volumetric flask.

  2. The aim of this experiment is to investigate the enthalpy change of combustion for ...

    This % error is stated in my plan. My final modified method using the flame calorimeter, which was made of glass, was the most accurate. However an anomalous result can be seen on graph two involving Propanol which has three carbon atoms in its main chain.

  1. The aim of this experiment is to produce Aspirin. This is an estrification in ...

    The solid gets hot when added to water Wear eye protection. Wear protective gloves. Avoid skin contact Results obtained were recorded in a table format:- Recrystalised aspirin Volume cm3 Accurate 1 Accurate 2 Accurate 3 Final Start NaOH used Concordant results Mass of aspirin used Accurate 1 = -------g Accurate

  2. investigating the amount of ascorbic acid present in fruit

    Place a funnel on top of the 50cm3 burette. 9. Get a clamp to hold the burette in a vertical position. 10. Rinse the 50cm3 burette with NBS solution because this prevents any inaccuracies and also because that is what will be used in the experiment.

  1. Comprehensive and Detailed Chemistry notes

    The principal sources of nitrogen oxides is emissions from vehicles. In the combustion chamber, nitrogen and oxygen combine to form nitric oxide. N2 + O2 � 2NO 2NO + O2 � 2NO2 describe, using equations, examples of chemical reactions which release sulfur dioxide and chemical reactions which release oxides of

  2. The Preparation of 1-bromobutane

    H �1/2 H H - C-H H �1/2 �1/2 �1/2 H-C - C - C -Br �1/2 �1/2 �1/2 H H H 2-methyl 1-bromobutane 4) CH3 �1/2 CH3 - C - CH3 �1/2 Br 2-bromo 2-methyl propane Uses of 1-bromobutane 1. It is used in the preparation of alcohols e.g.

  1. Synthesis of Cyclohexene by the Dehydration of Cyclohexanol

    4. The reflux flask was heated under a simple distillation and distillate were collected from temperature 65�C to 85�C. Distillate was collected in a boiling tube which stood in an ice bath. 5. The mixture started boiling at 60�C and its colour turned black.

  2. Comparison between Cyclohexane and Cyclohexene

    This is due to the fact that water molecules are polar while cyclohexene molecules are non-polar. They are not attracted to each other as hydrogen bonds cannot be formed. On the other hand, cyclohexane has no reaction with bromine water as the test tube is not exposed to the sunlight.

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work