Chemistry Lab Report

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chemistry lab report : reaction of alcohol

CHEMISTRY LAB REPORT
SK026

SEMESTER 2 SESSION 2011/2012

TITLE                 :REACTION OF ALCOHOL
DATE                 :
NAME                : 
MATRIC NO      : 
PARTNER          : 
PRACTICUM     : 
SUPERVISOR    : 

Title            : Reaction Of Alcohol
Objectives :
1. To classify alcohol
2. To study the chemical properties of alcohols
Introduction:
Alcohol is a class of organic compound containing hydroxyl group,     OH as the functional group. Alcohol can be classified as:         

                         H                                      H                                   H                           |                                         |                                     |      R ̶ C ̶ OH                        R  ̶ C  ̶ OH                      R  ̶ C  ̶ OH            |                                       |                                        |                           H                                     R                                      R Primary Alcohol(1 ̊)      Secondary Alcohol(2 ̊)       Tertiary Alcohol(3 ̊)

Lucas reagent, a mixture of concentrated hydrochloric acid and anhydrous zinc chloride, can be used to differentiate the three classes of alcohols. Tertiary alcohol turns cloudy or appears in two layers almost immediately, secondary alcohol reacts within 5 to 10 minutes whereas primary alcohol reacts very slowly.

Alcohol can be oxidised to aldehyde, ketone or carboxylic acid. The product formed depends on the class of alcohol used. Various oxidising agents such as KMnO₄, Na₂Cr₂O₇ and H₂CrO₄ can be used. The reaction between alcohols and carboxylic acids will produce esters.

Apparatus:
Stopper, dropper, test tube, stopwatch, water bath, measuring cylinder (10ml) Chemical Reagents:
Ethanol, n-Butanol, 2-Butanol, Alcohol X, Lucas reagent, 2-methyl-2-propanol, Concentrated H₂SO₄, 0.04 M Na₂Cr₂O₇, Glacial acetic acid

Procedure
(a)  Lucas Test
1.      1 mL of 2-methyl-2-propanol is placed in a test tube. 2.      2 mL of Lucas reagent is added into the test tube. 3.      The test tube is stopped and shook.
4.      The observation and the time taken for the reaction to occur are recorded. 5.      Step 1 until 4 are repeated using 2-butanol, n-butanol and alcohol X. The test tube that has no change is placed in a water bath at 70 ̊- 80 ̊C.

(b) Oxidation
1.      5 mL of 0.04 M Na₂Cr₇ solution is placed in the test tube. 2.      3 drops of concentrated H₂SO₄ is added to the solution in the fume cupboard. 3.      3 drops of n-butanol is added to the mixture and heated in a water bath at 70 ̊- 80 ̊C. 4.      Step 1 until 4 are repeated using 2-butanol, 2-methyl-2-propanol and alcohol X. 5.      The colour change is recorded.

(c) Esterification
1.      2 mL of ethanol is placed dry test tube.
2.      1 mL of glacial acetic acid and 3 drops of concentrated H₂SO₄ are added to the ethanol in the fume cupboard. 3.      The mixture is shook and placed in water bath at 60 ̊C for 5 to 10 minutes. 4.      3 mL of distilled water is added to the mixture. A whiff of the vapour released was taken.

Results:
(a) Lucas Test
Alcohol| Observation| Deduction|
2-methyl-2-propanol| The solution turn cloudy and 2 different layers are formed immediately| Tertiary alcohol| 2-butanol| The solution turn cloudy and 2 different layers are formed in 5min 30s| Secondary alcohol| n-butanol| The solution turn cloudy and 2 different layers are formed in 12min 13s| Primary alcohol| Alcohol X| The solution turn cloudy and 2 different layers are formed immediately| Tertiary alcohol|

(b) Oxidation
Alcohol| Observation| Deduction|
2-methyl-2-propanol| Orange colour remain unchanged| Not undergo oxidation| 2-butanol| Orange colour turns green and 2 layers are formed| Undergo oxidation| n-butanol| Orange colour turns green and 2 layers are formed| Undergo oxidation| Alcohol X| Orange colour...
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