Question
How will you detect the presence of bromine and iodine present in an organic compound by carbon disulphide test?
Solution
(i) Test for bromine and iodine. A small portion of Lassaigne's filtrate is acidified with dilute hydrochloric acid and few drops of carbon disulphide (or carbon tetrachloride) are added to it which forms a separate layer at the bottom. An excess of chlorine water is then added to it and shaken vigorously.
(a) An orange colour in carbon disulphide layer confirms bromine.
(b) Violet colour in the carbon disulphide layer confirms iodine.
