Description of experiment
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Needed compounds:
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hydrogen peroxide : H2O2
sodium hydroxide : NaOH
hydroquinone : HO C6H4 OH
Class:
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elem=C
photography
redox
Summary:
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Hydroquinone is not oxidized to the dark brown product by hydrogen peroxide
as it is done by oxygen from the air in alkaline environments.
Description:
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Dissolve some hydroquinone in water and add some hydrogen peroxide (3% by
weight): The liquid becomes pale pink (almost colorless) and remains clear.
Add some granules of NaOH: The solid dissolves and the liquid turns pale
yellow.
Add a large amount of water: The liquid now turns orange brown. On dilution
the dark oxidation product of hydroquinone in alkaline environments is formed.
Is this due to the presence of oxygen, dissolved in the added water, or is
this because of the hydrogen peroxide?????