Experiments for 'hydrogen peroxide'
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 'hydrogen peroxide':
EXPERIMENT 1
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Nitrous vapors react with thiocyanate, building a red/brown compound, which
disappears again, when left in contact with air.
EXPERIMENT 2
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Thiocyanate reacts with nitrogen dioxide to form a red/brown compound. It
does not react with nitrogen monoxide. When a reaction occurs with NO2,
a white fume is produced.
EXPERIMENT 3
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Vanadium(III) hydroxide apparently forms a precipitate and does not
dissolve in strongly alkaline liquids.
Vanadium (III) and (IV) are oxidized by peroxodisulfate to vanadium (V).
EXPERIMENT 4
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Hydrogen peroxide builds complexes with vanadium (IV) and vanadium (V)
species. These compounds are not stable and result in dissociation of
the complex and formation of vanadium (IV) compounds. The net result
of adding hydrogen peroxide to a solution containing vanadium (V) can
be reduction to vanadium (IV) with the formation of oxygen.
EXPERIMENT 5
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Vanadium (III) apparently builds a coordination complex with EDTA in
strongly acidic environments. This complex is brown.
EXPERIMENT 6
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Vanadyl builds an intensely colored complex with thiocyanate in acidic
environments. In alkaline environments this complex is destroyed.
When H2O2 is added, this complex is destroyed as well, but in this
case some heating is required.
EXPERIMENT 7
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Vanadium (IV) does not readily yield precipitates with alkaline compounds.
Carbonate is not capable of precipitating this.
Hydrogen peroxide builds a complex with vanadium (V) and possibly with
vanadium (IV). Diverse coloured compounds are formed in sequence. What
is their constitution?
EXPERIMENT 8
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Vanadyl ions do not form a special complex with tartaric acid in strongly
acidic environments.
When hydrogen peroxide is added, a complex is formed, but is
this due to the presence of tartaric acid?
When tartaric acid is added to a solution of vanadyl sulfate in an
environment, which is only slightly acidic, then a green complex is
formed. On making the liquid more basic, a vague sequence of color
changes occurs, through grey/blue, finally going to brown.
EXPERIMENT 9
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Vanadium (V) compounds form yellow compouds with hydrogen peroxide in
alkaline environments, with strong solutions and very high alkalinity grey
and blue compounds are formed, which, however, decompose easily.
EXPERIMENT 10
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Vanadium (V) is capable of forming many peroxo compounds, whose appearance
strongly depends on pH.
EXPERIMENT 11
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Without the help of a strong acid, vanadium pentoxide is not capable of
oxidizing formic acid, not even when heated. When some sulfite is added,
then incomplete reduction of the V2O5 can be observed.
With the help of a strong acid and when in solution, vanadium (V) is
capable of oxidizing formic acid, but only very slowly.
With formic acid and vanadium (IV), apparently a coordination complex
is formed. Another explanation is given below at the end of the
description.
EXPERIMENT 12
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Vanadium in its +4 oxidation state forms a blue compound, vanadyl, in acidic
environments. In near neutral to alkaline environments, the situation is
less clear. Reduction of neutral or alkaline vanadium (V) compounds yields
a dark and turbid liquid.
Vanadium in its +5 oxidation state gives light yellow compounds in mildly
alkaline environments. Al lowering the pH, the color becomes more intense,
until a maximum is reached. When the pH is lowered even more, then lighter
yellow compounds are formed again.
Vanadium (IV) cannot coexist with hydrogen peroxide. In alkaline media it
is oxidized to vanadium (V), which with excess peroxide gives a yellow
peroxo complex. In acidic media, vanadium (IV) is oxidized to vanadium (V)
which gives a deep brown/red peroxo complex with excess poroxide.
EXPERIMENT 13
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Copper (II) reacts with thiocyanate in a complex way.
EXPERIMENT 14
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Copper is oxidized by a mix of concentrated hydrochloric acid and
hydrogen peroxide. When the peroxide is used up and there is still an
excess amount of hydrochloric acid, then the copper (II) appears to
oxidize the copper metal, under the formation of an intensely colored
complex. (What is the constitution of this complex??)
When the solution is diluted with water, then the intensely colored
complex is destroyed and a white crystalline precipitate of CuCl is
formed. If too much water is used, then no clear precipitate is formed.
EXPERIMENT 15
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Copper (II) reacts with metallic copper, in the presence of a large amount
of hydrochloric acid, forming an intensely colored compound. This compound
contains copper (I). If copper (II) is used alone, with hydrochloric acid
and peroxide, then the strong coloration does not occur.
EXPERIMENT 16
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Hydroquinone is capable of reducing copper (II) to copper (I) in alkaline
environments. The copper is not reduced to its metallic form.
EXPERIMENT 17
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Copper builds higher oxides than CuO when strong oxidizing agents are
present in alkaline environments. Probably these are not copper (III)
compounds, but the oxo-ion probably is replaced by peroxo or superoxo.
EXPERIMENT 18
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Decomposition of hydrogen peroxide is catalyzed by cuprammine complex.
EXPERIMENT 19
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In alkaline environments, copper (II) shows remarkable behavior, when brought
in contact with strong oxidizers or reductors.
EXPERIMENT 20
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Copper builds a remarkable complex with ascorbic acid and is easily
reduced by ascorbic acid in alkaline environments. Copper (II) builds
a brown compound with hydrogen peroxide in alkaline environments.
EXPERIMENT 21
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Copper and nickel carbonates (basic), which do not dissolve in water, do
dissolve in ammonia, due to formation of a complex with ammonia.
Cobalt carbonate also dissolves, but now an additional reaction occurs,
taking up oxygen from the air.
EXPERIMENT 22
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Copper (II) builds a coordination complex with acetate ions. On addition
of hydrogen peroxide, this complex is destroyed and a new compound is
formed.
EXPERIMENT 23
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Copper (II) amine complex is reduced to a colorless copper (I) amine
complex by hydroxyl amine. The copper (I) complex is oxidized by oxygen
from the air very easily.
EXPERIMENT 24
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Copper (II) salts give a cyan precipitate with bicarbonates. The color of
this precipitate is the same as the color of commercially available basic
copper carbonate.
This precipitate reacts with hydrogen peroxide, forming a dark green/brown
compound. With sulfite it also reacts, forming a brownish compound, which
on acidification dissolves, forming a light yellow/brown clear liquid.
EXPERIMENT 25
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Copper (II) is reduced by metabisulfite / sulphur dioxide to a copper (I)
compound, but some heating is required in order to make this reaction
fast.
EXPERIMENT 26
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When copper (II) is present in hydrochloric acid, then it does not react
immediately with hydroxyl ammonium, some heating is required to have a
reaction, resulting in formation of a dark green/brown compound. When the
liquid is made alkaline with excess ammonia, then it quickly becomes
colorless, due to reduction of copper (II) to copper (I), which forms a
colorless complex with ammonia.
A very peculiar reaction occurs on oxidation by oxygen from air. The liquid
is covered by a very thin shiny layer, looking like a strongly coloured oil
on water. It is not clear what it is, more research is needed.
EXPERIMENT 27
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Copper (II) carbonate gives a very dark compound with H2O2, is this a
peroxide compound or just copper oxide?
EXPERIMENT 28
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Palladium (II) is not oxidized by H2O2 in acidic environments.
EXPERIMENT 29
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Titanium slowly dissolves in concentrated hydrochloric acid, forming deep
blue/violet titanium (III) ions. On addition of hydrogen peroxide these are
oxidized to titanium (IV), which in turn forms a deep red coordination
complex with hydrogen peroxide.
The deep red coordination complex is only stable in acidic to neutral media.
It also is easily reduced by nitrite. It is not affected strongly by
persulfate. With fluoride, a light yellow compound is formed, but the
formation of that may also be due to rise of pH.
EXPERIMENT 30
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Zinc (II) gives a white precipitate with ferrocyanide. This precipitate
becomes pale yellow, when treated with hydrogen peroxide (at least, when
in acidic environment).
EXPERIMENT 31
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Cobalt (II) appears to react with ammonia, but only when an oxidizer
is available. The resulting compound has an intense color.
EXPERIMENT 32
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Cobalt gives a green coordination complex with tartrates, when oxidized to
the +3 state.
EXPERIMENT 33
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Cobalt (II) gives a coordination complex with catechol (or is this due
to formation of a cobalt (III) complex with catechol????).
EXPERIMENT 34
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Cobalt (II) is stable in acidic environments, but in alkaline environments
in the presence of ammonia it reacts with oxygen from the air, resulting
in the formation of a dark red/brown coordination complex.
EXPERIMENT 35
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Cobalt (II) gives a precipitate with bicarbonate, which reacts with hydrogen
peroxide, probably forming a cobalt (III) compound.
EXPERIMENT 36
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Cobalt forms many complexes with ammonia and it forms these complexes
easily, but when cobaltosic oxide (Co3O4, black oxide) is used, then no
such reactions can be observed. Co3O4 appears to be very inert.
EXPERIMENT 37
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Cobalt (II) salts give a blue/green precipitate when dilute ammonia is added.
This precpitate is fairly stable towards air. When more concentrated ammonia
is used, then a dark brown compound is formed, but this compound is formed
by contact with air. On addition of hydrogen peroxide also a very dark
brown compound is formed.
When the pH is increased strongly, then the blue precipitate is not stable
anymore, instead a dark bright blue compound is formed, which, however,
quickly turns pink.
When a large amount of ammonia is replaced by ammonium, then the blue
precipitate is not formed anymore, but a coordination complex is formed,
which is very easily oxidized by oxygen from the air.
EXPERIMENT 38
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Cobalt sulfide does not dissolve in dilute acids and it does not dissolve
in concentrated hydrochloric acid (at least not easily). With the help of
hydrogen peroxide it is possible, however, to dissolve the compound.
EXPERIMENT 39
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Cobalt (II) gives a green precipitate with ferrocyanide and a dark red/
purple precipitate with ferricyanide. The green precipitate cannot be
converted to the red one by means of oxidation by hydrogen peroxide, but
another, dark blue, compound is formed.
EXPERIMENT 40
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The hexanitrito cobaltate (III) ion can be reduced by SO2 to cobalt (II),
but this reduction requires heating. Some brown compound remains, this
probably is due to the inertness of many cobalt (III) coordination
complexes. With nitrite, a brown complex is formed again. This differs
from the gold/yellow hexanitrito cobaltate (III).
EXPERIMENT 41
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The hexanitrito cobaltate (III) ion is affected by concentrated nitric
acid. It changes from yellow to brown. What is the nature of this change?
EXPERIMENT 42
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The hexanitrito cobaltate (III) ion is stable towards dilute sulphuric acid.
Addition of hydrogen peroxide also does not destroy the yellow complex.
EXPERIMENT 43
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In this experiment, some of Werner's experiments are repeated. Here it is
shown that cobalt forms beautifully colored carbonato complexes. The exact
complex formed, depends on the experimental conditions. It is remarkable
what kinds of reactions are shown by cobalt in its complexes and it is
really difficult to precisely determine what is happening and it even is
difficult already to get the same results without precisely specifying the
exact experimental conditions (e.g. using HCl instead of H2SO4 already
results in a different outcome).
EXPERIMENT 44
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Acetone can be mixed with water in any ratio, but when sodium hydroxide
is added, then the liquids are not miscible in any ratio anymore.
Sulphur reacts with acetone in the presence of sodium hydroxide. Sulfide
does not show such a reaction.
EXPERIMENT 45
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Sodium sulfide is oxidized by acidic hydrogen peroxide with extreme violence.
EXPERIMENT 46
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When molybdates are reduced, then intense blue compounds are formed. It
is believed that these intensely coloured compounds are multi-nuclear
Mo-compounds, with different nuclei having different oxidation states.
EXPERIMENT 47
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In strongly alkaline environments, molybdates are not as easily reduced
as in neutral or acidic environments.
EXPERIMENT 48
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Molybdate forms strongly colored, but unstable, complexes with hydrogen
peroxide.
EXPERIMENT 49
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Molybdate forms blue or green compounds, when reduced with mild reducing
agents or when little quantitities of reducing agents are used.
EXPERIMENT 50
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Molybdates and orthophosphates give a yellow complex, which is reduced more
easily than molybdates alone.
EXPERIMENT 51
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Hydroquinone is oxidized by hydrogen peroxide. This reaction is slow
in a neutral environment.
EXPERIMENT 52
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Ferric chloride enhances the oxidation of hydroquinone by hydrogen
peroxide considerably. Besides this, a coordination complex appears
to be formed when ferric chloride is added to an hydroquinone/peroxide
solution.
EXPERIMENT 53
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Diverse phenol-derivatives, can be oxidized easily by bromine, yielding
intensely colored oxidation products.
EXPERIMENT 54
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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.
EXPERIMENT 55
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Photography developers, based on phenol-like structures, are easily oxidized
by air in alkaline environments and the oxidation products are such, that
a reverse process does not occur anymore (probably the oxidation products
are large polymerized species).
EXPERIMENT 56
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Phenidone is oxidized by air, but is much less susceptible to oxidation
than developers, such as hydroquinone, pyrogallol.
EXPERIMENT 57
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It appears that copper (II) ions catalyse the oxidation of pyrogallol by
hydrogen peroxide.
EXPERIMENT 58
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The coordination complexes formed by iron-salts and phenol-like photographic
developers show very typical reactions with hydrogen peroxide. Many times
these reactions result in oxidation products which are not dark colored,
as opposed for oxidation by atmospheric oxygen.
EXPERIMENT 59
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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 60
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When hydroquinone is oxidized by hydrogen peroxide in acidic environments,
then a pale yellow compound is formed. This is in strong contrast with
oxidation by oxygen from air in alkaline environment, where a dark brown/
black compound is formed.
EXPERIMENT 61
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P-aminophenol, when oxidized, forms a deeply colored compound. The color
of this compound is deep blue/purple, but the environment and the used
oxidizer have some influence on the color of the liquid as a whole (other
compounds may make the color less pure).
EXPERIMENT 62
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Vanadium pentoxide catalyzes the oxidation of hydroquinone to quinone by
hydrogen peroxide.
EXPERIMENT 63
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Bromide is oxidized by hydrogen peroxide in acidic environments. Addition
of nitric acid strongly enhances the reaction.
EXPERIMENT 64
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Potassium bromate is capable of oxidizing hydrogen peroxide, itself being
reduced to bromine.
EXPERIMENT 65
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Selenium dissolves in a sulfide solution, forming a deep red/brown solution.
Hydrogen peroxide is capable of oxidizing this solution.
EXPERIMENT 66
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Rhenium is oxidized easily by nitric acid. The oxidation product is a color-
less compound, soluble in water (according to literature it is perrhenic
acid, HReO4). Perrhenic acid is not a really strong oxidizer. It can be
reduced by zinc, but addition of sodium sulfite does not result in formation
of the same compound.
Hydrogen peroxide is capable of oxidizing back to perrhenic acid, but some
light yellow compound remains. What is it?
EXPERIMENT 67
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Chromium (III) can be converted to chromium (VI) in strongly alkaline
environments.
EXPERIMENT 68
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Oxidation of chromium (III) to chromium (VI).
EXPERIMENT 69
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Chromium (III) can be oxidized to chromium (VI) by persulfate in alkaline
environments.
EXPERIMENT 70
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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 71
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Bleach is capable of oxidizing chromium (III) to its hexavalent state, but
this is not accomplished easily and completely.
EXPERIMENT 72
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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 73
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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 74
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Sodium dichromate dissolves in water very well, much better than potassium
dichromate. When it is reduced, then it is hard to crystallize a chrome
(III) salt or a mixed sodium chrome (III) salt.
EXPERIMENT 75
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From ice cold strongly alkaline solutions of potassium chromate, one can
create peroxochromate by adding hydrogen peroxide carefully.
EXPERIMENT 76
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Chromium (III) gives coordination complexes of all kinds of colours, when
formed from a redox reaction, starting with dichromate.
EXPERIMENT 77
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When dichromate is brought in contact with peroxide, then after an initial
transient, a green variation of chromium (III) is produced. This compound,
however, slowly changes to a bluish/violet compound.
EXPERIMENT 78
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When dichromate is reduced by means of adding hydrogen peroxide, then after
the initial transient a green compound is formed, even when the acid in
which the dichromate is dissolved is nitric acid (nitrate is supposed to
not form a coordination complex with chromium (III)). Is this green compound
a coordination complex with nitrate? or with hydrogen peroxide?
This coordination complex can easily be destroyed by heating.
EXPERIMENT 79
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Chromium (III) builds a nice brightly colored green complex with phosphates.
This compound has no bluish hue, like sulfate gives with chromium (III).
Chloride also builds a complex. Formation of these complexes is not on
simple addition of a chromium (III) salt to the corresponding anions.
Heating is required.
EXPERIMENT 80
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Dichromate reacts with hydrogen peroxide, also when no acid is present.
An initial compound is formed quickly, which decomposes slowly, releasing
heat. Due to heating up, the reaction proceeds faster and faster, until
all of the peroxide has been used up.
EXPERIMENT 81
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Chromic acid reacts with hydrogen peroxide under formation of a dark blue
compound. When more hydrogen peroxide is added, then apparently the pH of
the liquid becomes too high and other almost black compounds are formed,
which quickly decompose.
EXPERIMENT 82
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Dichromate reacts with hydrogen peroxide, yielding chromium (III) as the
final product, in acidic environments. In alkaline environments, chromium
(III) yields chromate with hydrogen peroxide.
EXPERIMENT 83
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Aniline gives colored compounds with chromium. The colors are remarkably
intense.
EXPERIMENT 84
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Manganese (II) ions apparently do not form coordination complexes with EDTA.
If they do so, then the coordination complex is (almost) colorless.
EXPERIMENT 85
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Manganese (II) forms a white precipitate with bicarbonate, while slowly
developing a gas (probably this is CO2). This precipitate is not quickly
oxidized by oxygen from the air. When the precipitate is made more alkaline
by adding hydroxide, then it is oxidized fairly quickly. Addition of
hydrogen peroxide causes immediate oxidation of the alkaline precipitate.
EXPERIMENT 86
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Sulfide is capable of forming a brightly coloured compound with antimony
(III) in a strongly acidic environment. The sulfide is not destroyed by
strong acid and is not converted to hydrogen sulfide gas.
EXPERIMENT 87
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Dichromate is quickly reduced by tin (II) ions.
Hydrogen peroxide does not show a visible reaction with tin (II) ions.
EXPERIMENT 88
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Silver (I) gives a precipitate with bicarbonate, which becomes yellow and
more compact on standing. With H2O2 a dark compound is formed, which
dissolves in nitric acid under formation of a gas. Is this dark compound
a higher oxide of silver (e.g. Ag2O2?).
EXPERIMENT 89
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Silver (I) ions, when treated with hydroxide give brown silver (I) oxide.
When hydrogen peroxide is added, then that is decomposed and the precipitate
of oxide does not change noticeably. When, however, hydrogen peroxide is
first mixed with a solution of a silver (I) salt and then the hydroxide is
added, then a black precipitate is formed. Probably this is finely divided
metallic silver.
EXPERIMENT 90
---------------
Acetone reacts with sulphur in strongly alkaline environments. What products
are formed?
A similar reaction is observed between methyl ethyl ketone and sulphur.
EXPERIMENT 91
---------------
Lead hydroxide is oxidized by hydrogen peroxide. The resulting compound
does not dissolve in dilute nitric acid.
EXPERIMENT 92
---------------
Thiosulfate gives a purple coordination complex with iron (III). This
complex, however, is not stable. With iron (II) no complex is formed.
Iron (III) is reduced by thiosulfate after the initial formation of
the purple coordination complex. This is shown by adding ferrocyanide,
which does not result in formation of an intense dark blue precipitate.
EXPERIMENT 93
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Ferricyanide gives a dark brown coordination complex with ferric ions. This
complex is soluble in water. It is easily transformed to the much more
stable, dark blue and insoluble ferroferricyanide.
EXPERIMENT 94
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The experiment described below suggests the formation of a coordination
complex between iron and ascorbate. The presence of the ascorbate induces
a completely different behavior of ferric/ferrous ions in alkaline
environments.
EXPERIMENT 95
---------------
Ferric ions apparently form a coordination complex with glucose in alkaline
environments. Normally ferric ions give a brown precipitate in strong
alkaline liquids, with glucose the liquid remains clear.
EXPERIMENT 96
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Aluminium (III) does not form colored compounds with ferrocyanide nor with
ferricyanide. Manganese (II) reacts with both of them, but a colored
compound is formed with ferricyanide only.
EXPERIMENT 97
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Ferrous sulfate is hard to dissolve cleanly in water. It usually is
contaminated with some oxidation products and in the water it is slowly
oxidized by air as well.
EXPERIMENT 98
---------------
Ferrocyanide and ferricyanide decompose on heating with dilute sulphuric
acid. When the decomposition product of ferrocyanide is treated with
hydrogen peroxide, then it looks very much like the decomposition product
of ferricyanide.
EXPERIMENT 99
---------------
Ferrocyanide can be oxidized by hydrogen peroxide easily. This redox
reaction makes the liquid alkaline: H2O2 + 2e --> 2OH-
EXPERIMENT 100
---------------
Ferrocyanide reacts with hydrogen peroxide, forming a fairly intensely
colored yellow compound (probably ferricyanide), but this reaction was
expected to make the liquid more alkaline, but this cannot be observed.
EXPERIMENT 101
---------------
Ferrocyanide in acidic environments reacts with bromine in a very peculiar
way. An extremely dark compound is formed. This reaction does not occur
in neutral environments and this cannot be observed with ferricyanides.
What is the dark compound? Is it a coordination complex or a condensation
product of many ferric/ferrous ions, close to formation of solid particles?
EXPERIMENT 102
---------------
Ferrous ions react with hydroxide, forming a light bluish/grey precipitate.
This precipitate, however, quickly turns brown.
EXPERIMENT 103
---------------
Ferrous ions react with H2O2. At low pH, the H2O2 oxidizes the ferrous ions
to ferric ions. At near neutral pH, a complex reaction occurs, the ferrous
ions are converted to some complex with the H2O2.
Ferric ions do not react with H2O2.
EXPERIMENT 104
---------------
Hydrogen peroxide probably serves as a reductor for an higher oxide of
nickel.
EXPERIMENT 105
---------------
Catechol appears to react with nickel (II), giving a coordination complex.
It is unclear, whether this is due to catechol itself or due to an
oxidation product, caused by oxidation by oxygen from air.
EXPERIMENT 106
---------------
Nickel in nickel (II) hydroxide is oxidized to a higher oxidation state by
hypochlorites, but not by chlorates. The oxidation product is reduced by
hydrogen peroxide and ammonia. Heating of the oxidation product makes it
more resistant to reduction and to breakdown by acids.
EXPERIMENT 107
---------------
Titanium metal slowly dissolves in concentrated hydrochloric acid and then
forms a very dark solution of a titanium/chloride complex. This solution is
much darker than an aqueous solution of titanium(III) in which the ions are
present as aqua complex.
With thiocyanate an even more intensely colored complex is formed. This complex
has the same color, but it is very dark.
EXPERIMENT 108
---------------
Thiourea is oxidized in acidic solution to formamidine disulfide, which exists
in solution as an acid salt. When a strong base is added, then the free base is
formed, but this at once decomposes. One of the decomposition products is
sulphur.
When excess oxidizer is used and the pH is increased strongly, then the sulphur
dissolves, giving rise to formation of polysulfides.
EXPERIMENT 109
---------------
Perchloric acid is very reluctant to reacting with many chemicals. This is
different from what many sites are telling. Perchloric acid only is extremely
reactive when it is anhydrous, the hydrous acid (60 ... 70%) is not that
reactive.
EXPERIMENT 110
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Chromium(III) oxide is extremely inert when it is calcined. It does not
dissolve in the common acids, nor in solutions of common bases. The solid,
however, can be oxidized by a solution of a bromate.
EXPERIMENT 111
---------------
Both oxone, active ion is HSO5(-), and peroxodisulfate, active ion is S2O8(2-),
produce a black precipitate when added to nickel(II) ions at high pH. Hydrogen
peroxide, on the other hand, only produces green nickel(II) hydroxide, and if
the black precipitate is present, it is destroyed by hydrogen peroxide, with
formation of oxygen and green nickel(II) hydroxide.
EXPERIMENT 112
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When a solution of copper sulfate is added to a solution of hydroxyl ammonium
chloride in dilute solution of NaOH, then a dirty green precipitate is formed.
At some places the precipitate becomes yellow. When the liquid is shaken, then
all of the precipitate dissolves and a colorless liquid is obtained. On
standing, a thin layer of solid material is formed on the surface of the
liquid. This layer has a dirty green color.
Hydroxyl amine reduces copper(II) at high pH and a colorless complex of
copper(I) is formed, which at really high pH becomes unstable with formation of
hydrous copper(I) oxide.
End of results for 'hydrogen peroxide'