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

Classifications of Alcohols Experiment

Extracts from this document...


Objective: 1. To differentiate different types of alcohol. Introduction: In organic chemistry, alcohols from the functional group of hydroxyl groups are organic compounds which are characterized by one or more hydroxyl (−OH) groups attached to a carbon atom of an alkyl group (hydrocarbon chain). Alcohols have the general formula CnH2n+1OH (where n represent the number of carbon atom in the compound) or R-OH (where R represent an alkyl group). Alcohols is usually classified into three classes, the primary alcohols (1°), secondary alcohols (2°) and tertiary alcohols (3°).Alcohols fall into different classes depending on how the -OH group is positioned on the chain of carbon atoms. In a primary (1°) alcohol, the carbon which carries the -OH group is only attached to one alkyl group. In a secondary (2°) alcohol, the carbon with the -OH group attached is joined directly to two alkyl groups. In a tertiary (3°) alcohol, the carbon atom holding the -OH group is attached directly to three alkyl groups. The attached alkyl groups may be from the combination of same or different groups. R = alkyl group The boiling points of the normal alcohols increase regularly with the increase of the molecular weights. The primary alcohols boil at a higher temperature than the secondary alcohols that are isomeric with them. Similarly, the latter have higher boiling points than their tertiary isomerides. ...read more.


When tertiary alcohol is tested in the other hand, the solution will turn cloudy immediately. The speed of this reaction is proportional to the energy required to form the carbocation. The reaction rate is faster when the carbocation intermediate is more stabilized by greater number of electron donating alkyl group (R-) bonded to the positively charged carbon atom while less substituted alcohol reacts much more slowly. Thus, a tertiary alcohol reacts fastest followed by secondary alcohol while primary alcohol generally reacts very slowly. From the experimental results obtained, we know that 2-methyl-2-propanol is a tertiary alcohol (3° alcohol) because this alcohol reacts immediately when Lucas reagent is added to form 2 layered-solution which is cloudy. 2-butanol is a secondary alcohol (2° alcohol) where it took around 7 minutes to form a cloudy solution while n-butanol and alcohol X are primary alcohols (1° alcohol) as they did not react significantly after 15minutes. The equations for the reactions of different alcohols used are as below:- 2-methyl-2-propanol (3° alcohol): ZnCl2 (CH3)3COH + HCl (CH3)3CCl + H2O (2-methyl-2-propanol) (2-chloro-2-methylpropane) 2-butanol (2° alcohol): ZnCl2 CH3CH(OH)CH2CH3 + HCl CH3CHClCH2CH3 + H2O (2-butanol) (2-chlorobutane / 2-butyl chloride) n-butanol (1° alcohol): ZnCl2 CH3CH2CH2CH2OH + HCl CH3CH2CH2CH2Cl + H2O (n-butanol) (1-chlorobutane / n-butyl chloride) Despite the fact that the experimental results obtained are accurate, 2-butanol took a longer time to react as compared to the theoretical results where it should react in within 5 minutes. ...read more.


Besides, addictive need to be added to the ester to produce a stronger pleasant, often fruit smell. Esters are widely used in the fragrance and flavour industry. It is also used in the organic chemistry for the test of alcohols and carboxylic acid. The equation of the chemical reaction that occurred is shown as follows: Concentrated HCl CH3CH2OH + CH3COOH CH3COOCH2CH3 + H2O (Ethanol) (Ethanoic acid) ? (Ethyl ethanoate) Precautionary steps: 1. Keep all the alcohols from any source of fire as alcohols are highly flammable. 2. All the unused or used waste materials must be poured into a specific waste container prepared in the fume chamber to prevent pollution to the environment. 3. Cautions must be taken when pouring concentrated sulphuric acid as it is toxic and is destructive to mucus membrane. 4. 2-methyl-2-propanol is harmful if inhaled. May cause skin and respiratory irritant. Severe eye irritant. 5. All transfer of chemicals should be done in the fume chamber to avoid inhalation of any chemicals vapour as it may cause severe sickness such as cancer. Conclusions: From the experiment, it can be concluded that n-butanol and the unknown alcohol X are primary alcohol, 2-butanol is a secondary alcohol and 2-methyl-2-propanol is a tertiary alcohol. Primary alcohol will undergo oxidation but react slowest in halogen substitution reaction. Secondary alcohol in the other hand undergoes oxidation reaction but will react with a medium speed under halogen substitution reaction. Tertiary alcohol will not undergo oxidation reaction but will react almost immediately in halogen substitution. Alcohols will react with carboxylic acid to form an ester. ...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. Marked by a teacher

    Experiment to determine the ethanol content of wine

    5 star(s)

    0.9835 0.9836 0.98355 11 0.9822 0.9818 0.98200 12 0.9806 0.9809 0.98075 13 0.9793 0.9794 0.97935 14 0.9779 0.9781 0.97800 15 0.9767 0.9765 0.97660 16 0.9752 0.9753 0.97525 17 0.9741 0.9737 0.97390 18 0.9724 0.9726 0.97250 19 0.9713 0.9711 0.97120 20 0.9698 0.9699 0.96985 Calibration Graph To Check the Accuracy of

  2. Marked by a teacher

    Reactions of aldehydes and ketones. The purpose of this experiment is to compare ...

    5 star(s)

    After pouring away the solution, there were white solid crystal remaining in the test tube. 5. For propanone, there wer 2 colourless immisible layers formed. 6. Both of the solution became turned warm. Part 2 Treating with 2,4-dinitrophenylhydrazine 7. 2,4-dinitrophenylhydrazine solution was yellow in colour.

  1. Preparation of haloalkane. The purpose of this experiment is to prepare 2-chloro-2-methylpropane from ...

    The pear-shaped flask was started to be heated and product from the fraction in the range of 47oC and 53oC was collected. 21. The volume of collected 2-chloro-2methylpropane was measured again using a measuring cylinder. The setup: Observations: 1. Concentrated hydrochloric acid, 2-methylpropan-2-ol and 2-chloro-2methylpropane were all colourless. 2.

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

    From this the amount of aspirin that reacted with the sodium hydroxide can be determined. Overall the aim of this investigation was to:- * To make Aspirin * To determine the purity of Aspirin prepared by using a number of techniques such as :- * Melting point determination * Forward

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

    wick so that when lit the size of the flame was 1cm in height and width. I then calculated the enthalpy of combustion for the readings and took the average of each alcohol. I then compared them to the values of enthalpy of combustion stated in a data book.

  2. Find the enthalpy change of combustion of a number of alcohol's' so that you ...

    x 100 E.g. Actual = - 500 Kj mol-1 Databook = - 1367 Kj mol-1 (867/1367) x 100 = 63.4% This shows a very high heat loss error. Risk Assessment: - There are risks within the experiment and it is essential that I have everything under control when dealing with potential hazards.

  1. Investigating the Enthalpy Changes of Combustion of Alcohols.

    It is known that branching an alcohol reduced the enthalpy of combustion (2), but why? Another possible source of error is the fact that some of the heat energy evaporated the water in the calorimeter, rather than just heating up the water.

  2. Comparing The Enthalpy Change OfCombustion Of Different Alcohols

    This is a random error. Below I have drawn a table to show the total error due to the measurements I took. Quantity measured % error calculation % error Total % error Mass of water+copper container 165.18g 2*(0.005/165.18)*100 0.006 Mass of fuel using balance 142.48g 2*(0.005/142.48)*100 0.007 3.09 Temperature change using thermometer 65 2*(1/65)*100 3.077

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