Description of experiment
Below follows a plain text transcript of the selected experiment.
Needed compounds:
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sulphuric acid : H2SO4
sodium persulfate : Na2S2O8
p-aminophenol HCl : NH2 C6H4 OH . HCl
metol : (CH3 NH C6H4 OH)2 . H2SO4
Class:
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elem=C
redox
Summary:
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Both metol and p-aminophenol HCl are oxidized by persulfate to colored
compounds. When metol is used, the color, however, is not as brilliant
and not as intense as when p-aminophenol HCl is used. Apparently the
methyl-group on the amino-part of metol has strong influence on the
color of the oxidation product or on the type of oxidation products.
Description:
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Add some p-aminophenol HCl and some sodium persulfate to dilute sulfuric
acid (appr. 7% by weight) and heat to appr. 60 C: An intense indigo/purple
compound is formed, the liquid becomes indigo/purple and remains clear.
Add some metol (n-methyl p-aminophenol sulfate) and some sodium persulfate
to dilute sulfuric acid (appr. 7% by weight) and heat to appr. 60 C: The
liquid turns pink/brown. The intensity of the color is much less than when
p-aminophenol is used.