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with several drops of sulfate acid. When shaking the test
tube, the change in the color of potassium permanganate is
not observed even when heated. What is it explained?
The ratio of homologs of benzene to a potassium
permanganate aqueous solution Homogenates of benzene
are readily oxidized by potassium permanganate. In this
case, the oxidation does not occur in the aromatic core, but
in the side chain with the formation of aromatic carboxylic
3
acids. Take 2 test tubes. In one, 2-3 cm of toluene is
poured into the one, and the other is as much 1,2-
3
dimethylbenzene (o-xylene). Each add 2 cm of a 0.5%
solution of potassium permanganate, acidified with a few
drops of sulfate acid. When shaking the tube and careful
heating it, the coloration of potassium permanganate
disappears and a brown precipitate MnO 2 is released.
Toluene is oxidized to benzoic acid by the equation of
reaction:

CH COOH
3
+ 2KMnO 4 + 2MnO + 2KOH
2

толуен бензойна кислота

1,2-Dimethylbenzene (o-xylene) in the oxidation of KMnO 4
forms phthalic acid by the equation of reaction:

CH COOH
3
+ 4KMnO 4 + 4MnO + 4KOH
2
CH COOH
3

o-ксилен о-фталева кислота