Description of experiment
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experiment.
Needed compounds: ----------------- bleach : NaClO sodium bromide : NaBr hydrochloric acid : HCl p-aminophenol HCl : NH2 C6H4 OH . HCl
Class: ------ elem=C,Br redox
Summary: -------- P-aminophenol HCl reacts with bromine and forms a purple compound.
Description: ------------ Add an excess amount of a solution of sodium bromide in HCl (10% by weight) to bleach: The liquid turns orange/red and a little amount of bromine vapor is observed above the liquid. In this way some acidic bromine water is prepared (excess bromide is of no concern here).
Add a solution of p-aminophenol HCl in HCl (10% by weight) to the freshly prepared acidic bromine water: No visible changes. Liquid remains orange.
Heat to appr. 60 C: The liquid turns purple. The purple color differs from the color, when p-aminophenol HCl is oxidized by e.g. persulfate or permanganate. In this experiment with bromine it is red/purple, in the experiment with persulfate, hydrogen peroxide and permanganate it is indigo/purple.
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