Experiments for 'chrome alum'
Below follows a summary of all experiments, matching your search. Click one of the EXPERIMENT hyperlinks for a complete description of the experiment.
Results for 'chrome alum':
EXPERIMENT 1
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A large set of compounds is checked on interaction with concentrated
nitric acid. Many reductors react violently with nitric acid.
EXPERIMENT 2
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Cr (III) reacts with the hexacyanoferrate (II) and hexacyanoferrate (III).
EXPERIMENT 3
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Chromium (III) can be converted to chromium (VI) in strongly alkaline
environments.
EXPERIMENT 4
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Oxidation of chromium (III) to chromium (VI).
EXPERIMENT 5
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When Cr3+ is added to an aqueous solution of ammonia, then a precipitate
is created, which does not dissolve on addition of much more ammonia.
EXPERIMENT 6
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Cr(III) can be reduced to Cr(II) by a zinc nail. On reoxidation to Cr(III)
a coordination complex appears to be created, both with sulfate and with
chloride.
EXPERIMENT 7
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Chromium (III) can have many different colors, depending on how it is
created and with which it coordinates.
EXPERIMENT 8
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Chromium (III) can be oxidized to chromium (VI) by persulfate in alkaline
environments.
EXPERIMENT 9
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Chromium (III) does not quickly build a coordination complex with ammonia,
such as is the case with copper (II) and nickel (II). Even in a slightly
alkaline environment of dilute ammonia, chromium (III) can be oxidized to
chromium (VI) by the action of hydrogen peroxide. Reduction, back to
chromium (III) is not easily accomplished in alkaline environment.
EXPERIMENT 10
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Bleach is capable of oxidizing chromium (III) to its hexavalent state, but
this is not accomplished easily and completely.
EXPERIMENT 11
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EDTA builds pink complexes with chromium (III). This complex is destroyed
in strongly alkaline environments.
EXPERIMENT 12
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Chromium (III) is oxidized to dichromate (chrome (VI)) by persulfate. This
reaction is catalyzed by silver (I).
EXPERIMENT 13
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When chromium (III) is created by reduction from dichromate with acidified
sulfite, then a green ion is formed. When acidified sulfite is added to
violet chromium (III), then the ions remain violet.
Apparently the way of creating chromium (III) determines its color (and
hence to what it is coordinated).
EXPERIMENT 14
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Chromium (III) builds a green coordination complex with metabisulfite,
not with thiosulfate.
When hydrogen peroxide is added, then the complex with metabisulfite is
destroyed.
EXPERIMENT 15
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Chromium (III) apparently builds a coordination complex with hydroxyl amine,
but this complex does not simply form from chromium (III) salts and
hydroxyl amine. If chromium (III) is formed by means of reduction of
chromium (VI) in the presence of hydroxyl amine, then the complex is
formed. If hydroxyl amine is added to chromium (III) without redox reaction,
then another complex is created.
EXPERIMENT 16
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Chromium (III) builds a coordination complex with nitrite of a fairly
intense purple color.
EXPERIMENT 17
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Chromium (III) builds a purple complex with EDTA, both when it is created
from dichromate and when it already exists and is brought in contact with
EDTA. When the pH is too low (or is this due to formation of a complex with
sulfate?), the formation of the complex does not occur.
EXPERIMENT 18
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Bisulfite and sulfite form coordination complexes with chromium (III). The
exact behaviour strongly depends on the pH of the solution.
When the pH is raised with sulfite and then decreased again with sulphuric
acid, then the color does not revert to the original color of aqueous
chromium (III). Probably a new compound is found, which is inert and does
not fall apart quickly in acidic environments.
EXPERIMENT 19
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Chromium (III) builds a coordination complex with sulfate in the heat.
This coordination compound does not crystallize well.
EXPERIMENT 20
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Chromium (III) forms a lavender precipitate, when combined with hydroxyl
amine in alkaline environments. This compound does not dissolve in
strongly alkaline environments.
EXPERIMENT 21
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Chromium (III) cannot be oxidized to chromium (VI) by vanadium (V) species
or bromates in strongly alkaline environments. Peroxodisulfate is capable
of achieving this.
EXPERIMENT 22
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Chromium (III) forms a purple coordination complex with nitrite. This
complex has a fairly bright pink/purple color, which differs quite a lot
from the color of aqueous chromium (III).
EXPERIMENT 23
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Chromium (III) is not reduced to chromium (II) by borohydride. Alkaline
chromium (VI) is only reduced slowly by borohydrode. On acidification the
reduction goes at once, but no further than the +3 oxidation state.
EXPERIMENT 24
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Benzotriazole is not oxidized by air. Apparently it forms a coordination
complex with chromium (III).
EXPERIMENT 25
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Pyrogallol gives rise to many colored products on oxidation and coordination.
More investigation is needed in order to get more insight in all these
colors and the conditions under which they are formed.
EXPERIMENT 26
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When p-aminophenol is oxidized in an acidic environment, then a compound
is formed, with a deep indigo/purple color.
EXPERIMENT 27
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Chromium(III) ions give a light green precipitate with iodate.
EXPERIMENT 28
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When hydrated sulfate-salts are heated, which only loose water, then their
properties strongly change. The color changes, but also the solubility
properties change a lot. The sulfate salts loose water easily, but no acid
(H2SO4 or SO3).
End of results for 'chrome alum'