DETECTION OF GLYCEROL PRESENT IN GIVEN ORGANIC COMPOUND

Experiment No. 14: DETECTION OF GLYCEROL PRESENT IN GIVEN ORGANIC COMPOUND

OBJECTIVE:

TO IDENTIFY THE ORGANIC COMPOUND PRESENT IN THE GIVEN ORGANIC SAMPLE

APPARATUS REQUIRED

1. Watch glass
2. Tong
3. Burner
4. Porcelain basin
5. Beaker
6. Test tube

CHEMICALS REQUIRED

• Given organic sample
• Blue and red litmus paper
• Other reagent

THEORY

Organic compounds are hydrocarbon and their derivatives. They are mainly made up of two parts- alkyl and functional group part. The functional group is defined as the atom or group of atoms that determines the characteristic properties of the organic compound. Some examples of functional groups are -OH, -CHO, -COOH, etc.

PROCEDURE

First of all, a preliminary test was performed. Then confirmatory test was done to identify the given organic compound.

OBSERVATION

1. Preliminary test:

a. Solubility: Soluble in water
b. Odour: Odourless
c. Colour: Colourless
d. Litmus paper test: Neutral
e. Residue test :

Experiment	Observation	Inference
Residue/Evaporation test: A few drops of the solution were evaporated on the watch glass over the water bath.	A sticky and viscous residue was formed.	May be glycerol.

Confirmatory Test

Test of glycerol

Experiment	Observation	Inference
1. Acrolein test: 2 ml of the original solution was taken in a clean and dry test tube and a pinch of KHSO4 or a few drops of conc. H2SO4 was added and warmed.	An irritating smell was formed.	Presence of glycerol
2. Tollen’s test: 2 ml of original solution was taken in a clean and dry test tube and 2 ml of Tollens reagent was added to it. The solution was heated in a hot water bath for 4-5 minutes.	A silver mirror was formed in the inner wall of the test tube.	Presence of glycerol.
3. Borax-phenolphthalein test: 2 ml of original solution was taken in a clean and dry test tube and 2 ml of borax solution was added to it. Then 2 drops of phenol phthalein solution were added and shaken well.	The pink colour disappeared on the addition of OS and reappeared on warming.	Presence of glycerol

Reactions involved

1. Acrolein test

2. Tollen’s test

3. Borax-phenolphthalein test

RESULT

Hence, glycerol was found in the given solution.

CONCLUSION

Hence, organic compounds can be tested using specific reagents.

PRECAUTION

1. Apparatus should be handled carefully.
2. The sample should be taken in small amounts.
3. Heating should be done carefully.

Structure:

IUPAC name: Propan-1,2,3-triol
Common name: Glycerol