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Testing for organic compounds

The table below shows the observations when a reaction occurs with organic compounds using certain tests. Make sure you can remember that is observed during these tests.

Organic compoundTest using bromine waterTest using acidified potassium dichromate solutionTest using magnesium ribbon
AlkanesRemains orangeRemains orangeNo fizzing
AlkenesChanges from orange to colourlessRemains orangeNo fizzing
AlcoholsRemains orangeSolution changes from orange to greenNo fizzing
Carboxylic acidRemains orangeRemains orangeFizzing
Organic compoundAlkanes
Test using bromine waterRemains orange
Test using acidified potassium dichromate solutionRemains orange
Test using magnesium ribbonNo fizzing
Organic compoundAlkenes
Test using bromine waterChanges from orange to colourless
Test using acidified potassium dichromate solutionRemains orange
Test using magnesium ribbonNo fizzing
Organic compoundAlcohols
Test using bromine waterRemains orange
Test using acidified potassium dichromate solutionSolution changes from orange to green
Test using magnesium ribbonNo fizzing
Organic compoundCarboxylic acid
Test using bromine waterRemains orange
Test using acidified potassium dichromate solutionRemains orange
Test using magnesium ribbonFizzing

These tests can be used to distinguish between different organic compounds.