Experiments for 'S'
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 'S':
EXPERIMENT 1
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Sulfide reacts with metavanadates, resulting in the formation of a dark
brown/greenish compound.
EXPERIMENT 2
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Vanadium pentoxide dissolves in concentrated sulphuric acid with some heating.
A deep red liquid is formed, which, remarkably, only is reduced by sulfite in
the presence of some water.
EXPERIMENT 3
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When vanadyl sulfate is dehydrated by heating, then the resulting solid only
dissolves partially in water and in dilute acid. When a strong oxidizer is
present, all of the solid dissolves again, forming a soluble vanadium species
in the +5 oxidation state.
EXPERIMENT 4
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Palladium (II) is not easily reduced by mild reducing agents. Only very
strong reductors are capable of reducing this to metallic palladium.
Strong oxidizers probably are capable of oxidizing palladium (II) to a
higher oxidation state, but if this is true, then the higher oxidation
state has almost the same color.
Sulfite, instead of reducing palladium to the metallic state, appears to
form a brightly colored coordination complex in acidic environments.
EXPERIMENT 5
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Bismuth forms a yellow complex with thiosulfate. In the presence of
thiosulfate, it still forms a deep orange complex with iodide, just as without
thiosulfate.
EXPERIMENT 6
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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 7
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The hexanitrite cobaltate (III) ion is strongly affected by sulfide. A black
compound is formed. On acidification of this, remarkably, no hydrogen
sulfide is formed. Probably the black compound is a compound containing
sulfide and nitrite in a single compound, which on acidification results
in oxidation of the sulfide.
EXPERIMENT 8
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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 9
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Sulphur dissolves in a solution of a sulfide. Polysulfides are formed.
EXPERIMENT 10
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Sulfide gives precipitates with some metals, which do not dissolve in
strong acids. These sulfides, however, can easily be dissolved, when an
oxidizing agent is used.
Sulfide is easily oxidized by moderately strong oxidizers.
EXPERIMENT 11
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Sulphur dissolves in hot solutions of sodium hydroxide and disproportionates
in a way, similar to disproportionating of halogens.
When acetone is added, a peculiar blue/green compound is formed in the
acetone. What is this compound?
EXPERIMENT 12
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This sequence of experiments shows that sulfite is capable of reducing
silver (I), copper (II) and iron (III), but that these reactions all
show their own peculiarities. Sulphur in the +4 oxidation state is a
mild reductant.
EXPERIMENT 13
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Sodium sulfide is oxidized by acidic hydrogen peroxide with extreme violence.
EXPERIMENT 14
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Iodide ion and sulphur dioxide form a deep orange/yellow complex at high
concentration. At somewhat lower concentration this complex looks deep yellow.
The complex formed in this experiment is {I.nSO2]-.
EXPERIMENT 15
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Thionyl chloride quickly hydrolyses in the presence of water.
EXPERIMENT 16
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Iodide ion reacts with thionyl chloride, most likely giving iodine, and some
sulphur(II) species.
Potassium bromide does not dissolve in thionyl chloride (at least, not visibly).
No reaction occurs.
EXPERIMENT 17
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Potassium dichromate is sparingly soluble in thionyl chloride, giving an
intensely colored red/orange/brown solution, which on addition to water
at once becomes green with a blue hue.
Potassium chromate does not dissolve in thionyl chloride. The solid changes
color from yellow to yellow/orange, and the solution becomes slightly colored,
but this faint reaction may be due to minor impurities in the potassium
chromate or thionyl chloride. If any potassium chromate dissolves, then it
is a very small amount.
EXPERIMENT 18
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Thionyl chloride is not soluble in concentrated sulphuric acid, or only
sparingly soluble.
The mix of thionyl chloride and sulphuric acid is capable of forming chromyl
chloride from potassium dichromate.
EXPERIMENT 19
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Niobium pentachloride is soluble in thionyl chloride, but not very well. Also,
such a solution becomes turbid.
EXPERIMENT 20
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Hydroquinone is a very strong reductor in alkaline environments. Oxygen
from the air is readily absorbed by an alkaline solution of hydroquinone.
Sulfite, however, makes an alkaline solution of hydroquinone much more
stable, because of formation of special hydroquinone/sulfite compounds.
EXPERIMENT 21
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Metol is easily oxidized by oxygen from the air, when dissolved in alkaline
media. When sulfite is present, however, oxidation does only occur at a
low rate.
EXPERIMENT 22
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Potassium chlorate is able to liberate bromine from a bromide. Reaction
with sodium sulfide of the bromine shows formation of fumes/smoke.
EXPERIMENT 23
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When potassium bromate and sulphur are mixed, then a very dangerous mixture
is created. This mixture, when ignited, produces an intensely bright flame.
EXPERIMENT 24
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A large amount of sulphur can be added to bromine, before a solid remains in
the liquid bromine. The sulphur dissolves in the bromine very easily.
EXPERIMENT 25
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Potassium chlorate and sulphur form a potentially explosive mixture, which
is quite sensitive to shock.
EXPERIMENT 26
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Persulfate decomposes in strongly alkaline environments.
EXPERIMENT 27
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When concentrated sulphuric acid is added to concentrated nitric acid,
then some heating can be observed.
The mixed acid reacts with tissue, but not as strongly as pure sulphuric
acid does. The mixed acid reacts with copper, but this reaction is not
as strong as the reaction with nitric acid only.
With citric acid and acetone no strong reaction occurs.
EXPERIMENT 28
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Nitric acid, mixed with sulphuric acid is a strong oxidizer. It is capable
of oxidizing iodine to iodate.
EXPERIMENT 29
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Cadmium selenide reacts vigorously with nitric acid, producing nitrous
fumes and a yellow/orange solid, which is filled with many small gas bubbles
and hence remains floating on the liquid.
Cadmium sulfide gives a similar reaction, but now a pale yellow solid is
formed. This yellow solid is sulphur.
EXPERIMENT 30
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Cadmium ions give a precipitate with sulfide at very low concentration
of free sulfide ions. Only at very low pH, cadmium ions and hydrogen
sulfide can coexist in solution at appreciable concentration.
A very similar effect can be seen with combinations of cadmium and
selenide.
EXPERIMENT 31
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Chromium (III) can be oxidized to chromium (VI) by persulfate in alkaline
environments.
EXPERIMENT 32
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Chromium (III) is oxidized to dichromate (chrome (VI)) by persulfate. This
reaction is catalyzed by silver (I).
EXPERIMENT 33
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When dichromate is added to sulfide, then a transient highly coloured
compound is formed, immediately followed by reduction to green chromium (III)
in alkaline environment.
EXPERIMENT 34
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This experiment shows two things:
1) Permanganate can be reduced by metabisulfite, but the reduction does
not proceed instantaneously when no additional acid is used.
2) Manganese sulfide is a dirty pink substance (color of flesh).
EXPERIMENT 35
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Silver is coordinated by thiosulfate. The silver-thiosulfate complex does
not show any of the reactions of free aqueous silver (I).
EXPERIMENT 36
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Silver chloride and silver oxide dissolve in a solution of sodium
thiosulfate. The reaction is not very fast.
EXPERIMENT 37
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Silver (I) ions form a precipitate, both with ferrocyanide and with
ferricyanide. The precipitate with ferricyanide is decomposed by alkalies,
the precipitate with ferrocyanide is more stable. Both compounds are
attacked by thiosulfate, which complexes the silver and causes the
solid to dissolve again.
EXPERIMENT 38
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Silver (I) ions give a dark brown precipitate with sulfide.
EXPERIMENT 39
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Acetone reacts with sulphur in strongly alkaline environments. What products
are formed?
A similar reaction is observed between methyl ethyl ketone and sulphur.
EXPERIMENT 40
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Ferrous sulfide is a black precipitate, which easily dissolves in acid.
EXPERIMENT 41
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Iron (III) gives a precipitate with S2-, but a redox reaction, resulting
in the formation of sulphur also appears to occur.
EXPERIMENT 42
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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 43
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Ferric ions form a coordination complex with sulfite.
EXPERIMENT 44
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A mix of aluminium powder and potassium permanganate is hard to ignite. When a
small amount of sulphur is added, then the mix is easily ignited, and a very
bright and fast burning flash is produced.
EXPERIMENT 45
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When sodium sulfide and sodium nitrite are mixed as solids, or when mixed in
aqueous solution, no reaction occurs. Sulfide ion and nitrite ion can coexist
in solution.
When a very small amount of acid is added, a bright yellow/ochre solid compound
is formed, which slowly turns lighter. When more acid is added, then the solid
becomes almost white.
The very light yellow, almost white compound most likely is very finely divided
elemental sulphur. The much brighter yellow/ochre definitely is not sulphur,
its color is too strong and also differs quite a lot from the kind of yellow of
sulphur.
EXPERIMENT 46
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Copper(II) ion and sulfite ion react in aqueous solution. A dirty green/yellow
precipitate is formed when solutions with these ions are mixed. When there is
excess sulfite, then on slight heating the precipitate redissolves and the
liquid becomes colorless.
Apparently a coordination complex is formed with copper(I). This coordination
complex is very air-sensitive. It reacts with air, giving a dirty
brown/green/yellow precipitate.
EXPERIMENT 47
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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).
EXPERIMENT 48
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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 49
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Copper(II) ions form no complex with tetrathionate ion and there also is no
formation of a precipitate. Even boiling does not cause a visible change.
EXPERIMENT 50
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Acetyl chloride is capable of dehydrating copper(II) chloride, and it even is
capable of replacing sulfate ion by chloride, itself being converted to acetyl
sulfate.
EXPERIMENT 51
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Iodine dissolves in thionyl chloride. It does not react. It gives a purple
solution, looking very similar to a purple solution of iodine in an alkane or
chlorinated hydrocarbons.
When water is added, then a remarkable reaction occurs. Sulphur is formed.
EXPERIMENT 52
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Sulphur dissolves in carbon disulfide exceedingly easily.
EXPERIMENT 53
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Sodium sulfite reacts vigorously with 68% nitric acid.
EXPERIMENT 54
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Sulphuric acid and acetic anhydride react with each other. This reaction is
very violent. The final product is a very viscous colorless liquid. The main
constituent of this liquid is acetyl sulfate or acetyl bisulfate.
EXPERIMENT 55
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Red phosphorus dissolves in concentrated sulphuric acid, when it is strongly
heated.
EXPERIMENT 56
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Triethylamine frequently is used in reactions, where thionyl chloride is used,
in order to capture any HCl formed in the reaction. However, when the only
reactive compounds are thionyl chloride and triethylamine, then these two
compounds react by themselves, giving rise to formation of black material,
which sticks to the glass and is difficult to remove.
EXPERIMENT 57
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Potassium bromate reacts with aluminium powder with a very bright light and
with crackling noise, but the mix is not like flash powder. Some sulphur is
needed for easy ignition of the mix.
When a tiny amount of red phosphorus is added to the mix, then it is ignited
even more easily, but then it also burns exceptionally fast, almost
explosively.
EXPERIMENT 58
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Antimony trioxide dissolves in hydrochloric acid, giving a colorless solution.
When hydrogen sulfide is passed through such a solution, then a small amount of
a yellow precipitate is formed and the liquid becomes very pale yellow.
On dilution, much more precipitate is formed and the surprisingly, the color
shifts from pale yellow to orange. The orange solid must be hydrous Sb2S3.
EXPERIMENT 59
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Arsenate does not form thioarsenates when sulfide ion is added. On
acidification, the sulfide is oxidized though by the arsenate.
EXPERIMENT 60
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Sulfur is an extremely fascinating element in that it is capable of existing in
a wide range of oxidation states under normal conditions, from -2 (as in
Hydrogen sulfide) up through +6 (sulfuric acid). The following experiment
demonstrates simple redox chemistry involving Sulfur dioxide gas created in
situ.
EXPERIMENT 61
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The tetrathionate ion is much more stable than the thiosulfate ion in acidic
solution.
EXPERIMENT 62
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Peroxodisulfate ion gives a deep brown complex with silver ions in nitric acid.
Oxone (peroxomonosulfate) does not give such a complex, actually, it quickly
destroys such a complex.
EXPERIMENT 63
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Dichromate ion oxidizes thiosulfate easily in acidic media, but in neutral
media it only is oxidizing incompletely, and a solid compound is formed.
EXPERIMENT 64
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Iodine dissolves somewhat in chlorosulfonic acid with a brown color.
EXPERIMENT 65
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A solution of tetrathionate reacts with nitrite in acidic solution. A green
compound is formed, which however is unstable and after a few minutes, the
solution decomposes. It becomes turbid and light yellow. Most likely the yellow
material is finely divided sulphur.
EXPERIMENT 66
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The combination of acetyl and sulfate, either directly, or derived from other
compounds reacts extremely energetically with water. It is remarkable that it
is this specific combination of three entities which gives extremely violent
reactions. This effect is demonstrated with different chemicals in different
combinations.
EXPERIMENT 67
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Sodium sulfite is not capable of reducing CrO3, dissolved in acetyl chloride.
As soon as water is added, the red color of the hexavalent chromium disappears
and green/blue trivalent chromium is formed.
EXPERIMENT 68
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Arsenic in oxidation state +5 is not easily reduced to elemental arsenic,
except by tin(II) chloride.
EXPERIMENT 69
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Thionyl chloride and copper nitrate react with each other, giving gaseous
products and solid anhydrous copper(II) chloride remains behind.
EXPERIMENT 70
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A mix of potassium perchlorate and sulphur cannot easily be ignited. When just
a tiny pinch of red phosphorus is mixed in, then the mix is ignited very easily
and it burns very fast with a bright flash.
EXPERIMENT 71
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When thiosulfate ion and nitrite ion are brought together in solution, then
nothing happens. When the solution is acidified, then a remarkable reaction
occurs. The liquid then quickly turns dark brown and remains clear. Immediately
after that, a colorless gas is produced and the color becomes lighter. The
color goes from dark brown through brown/orange and yellow to lime green. The
liquid remains clear and lime green for a few minutes and then it slowly
becomes turbid.
EXPERIMENT 72
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Antimony trioxide does not dissolve in concentrated nitric acid, not even when
the liquid is heated to boiling. When some hydrochloric acid is added as well,
then it quickly dissolves, producing a colorless gas as well. It is oxidized to
the +5 oxidation state.
When this solution is diluted, then a white precipitate is formed. This white
precipitate must be hydrous Sb2O5. When a dilute solution of sodium sulfide is
added to this still strongly acidic solution, then H2S bubbles out of solution,
but also a lot of precipitate is formed, which has a beautiful bright
orange/red color.
EXPERIMENT 73
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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 74
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Chlorosulfonic acid is an extremely reactive compound. It reacts violently with
many salts of oxoacids.
EXPERIMENT 75
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A clock reaction that precipitates antimony sulfide.
EXPERIMENT 76
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Carbon disulfide slowly reacts with an aqueous solution of sodium sulfide. The
resulting solution finally becomes deep orange.
End of results for 'S'