Qualitative analysis of unknown organic compound/s for preliminary tests.

EXPERINMENT 02

Object

Qualitative analysis of unknown organic compound/s for preliminary tests.

Reference

  1. Vogel Arthere, Elementary practical organic chemistry, 2nd edition, 1966, published by CBS publisher, page No. 61-64.
  2. Agarwal O.P., Practical Organic chemistry, published by Krishna educational publisher, Edition 2014, page no. 31-32.

Requirement

Test tube, spatula, different compound, glass-rod etc

Theory

Preliminary qualitative analysis of an unknown organic compound involves initial tests to determine the compound’s general properties and the presence of specific elements and functional groups. These tests include physical examination, solubility tests, and flame tests.

  Test Observation Inferences
1 (a)  Nature i)   Solid Carbohydrate, acid, phenol, amine , higher hydrocarbon may be present.
ii)   Liquid Alcohol , ketone , aldehyde, ester, phenol, amines may be present. 
2 (b)  Colour Yellow -Solid m- Dinitrobenzene, p- Nitro toluene, nitro phenol , nitro aniline
Yellow -liquid Nitrobenzene.
Brown P – Toluidine , resorcinol.
Blackish α – Naphthol
Pink ß – Naphthol
Buff or reddish Aniline, phenol, Aromatic amine.
Colourless Simple acid , alcohol, ester, ketone aromatic hydrocarbon.
3 Odour Carbolic Phenol, cresol.
Fishy Amine
Sweet pleasant Ester, alcohol and halogen derivatives.
Bitter almonds Nitrobenzene,Benzaldehyde
Moth balls Naphthalene
No particular  smell Aromatic acid ,amide, carbohydrate
   
4 Flame Test Sooty flame Aromatic compound or aliphatic compound containing small proportion of hydrogen e.g . CHCI3,CCI4
Non sooty flame Aliphatic compound
Substance chars Carbohydrate, sulphanilic acid.
5 Test  for  unsaturation

1. KMnO4 test. Substance + 2 ml of water shake well + 2 drops of dilute KMnO4 solution

Decolourisation of KMnO4 Saturated compound.
No decolourisation Unsaturated compound.

 

Result: Qualitative analysis of unknown organic compound/s for preliminary tests was done successfully.

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