Qualitative Analysis

For Organic Substances

Test for alkene functional group (Unsaturation Test)

Bubble/Shake the sample with aqueous bromine. If the C=C functional group is present, the brown aqueous bromine will decolourise

Test for alcohol function group (Oxidation Test)

Heat the sample under reflux with acidified potassium dichromate (VI). If the –OH functional group is present, the orange potassium dichromate (VI) will turn green

Test for acid functional group (Acidity Test)

Test with a pH meter OR test with universal indicator and compare against colour chart. If the substance is acidic, it will read a pH value of less than 7.0 (Alternatively, test with a carbonate and look for effervescence)