Science made alive: Chemistry/Experiments

Experiments, lexicographically ordered

On this webpage, the experiments are ordered lexicographically by means of the most important chemical element, investigated in the experiment. All chemicals, required for the experiment are mentioned as well, so one can see at once, what is needed to perform the experiment. Compounds, mentioned in green are not really required for the experiment itself, but are needed for safe disposal or cleanup.

The webpages, marked with an asterisk (*), are fully worked out. The other webpages are not completely worked out pages, but they definitely can be used as a basis for interesting ideas.

	element	required compound	link to experiment
	Ag	AgNO₃ NaOH NH3 (5%) organic reductor, e.g. glucose or glycerol	Formation of a silver mirror. A shiny silver mirror is prepared from a mix of an ammoniacal silver solution and a reducing organic.
*	Ag	AgNO₃ HNO₃ (dilute) CaC₂ ("carbide")	Preparation of a high explosive . Acetylene gas is bubbled through an acidic solution of silver nitrate. Silver acetylide is formed under these conditions.
*	Ag, Mg	AgNO₃ Mg (powder)	Water-initiated light and smoke . A mix of silver nitrate and magnesium powder is ignited with some water.
*	Ag	Na₂S₂O₈ HNO₃ (dilute) AgNO₃ (or Ag₂O) NaOH	Very high oxidation state of silver with persulfate. Silver(I) ions are oxidized to the +3 oxidation state with persulfate.
*	Al, Cu, Cl	Al (foil) NaCl CuSO₄·5H₂O HCl (10%)	Influence of combination of copper ions and chloride ions on reactivity of aluminium. A violent reaction only occurs, when both type of ions are present.
*	B	H₃BO₃ CH₃OH CH₃CH₂OH	Green fire . Methanol, or ethanol, in which some boric acid is dissolved, burns with a bright green flame.
	B	NH(CH₃)₂·BH₃	Green fire with boron compound. Dimethyl amine borane complex burns with a green flame.
*	Ba	BaCO₃ (cheap pottery grade) HCl (dilute, but fairly pure grade) H₂O₂	Preparation of barium chloride from potteries grade barium carbonate. A procedure for making good grade barium chloride, suitable for chemical experiments and qualitative analysis, is presented in this webpage.
*	Ba, Cs	KBrO₃ S₈ any soluble Ba-salt any soluble Cs-salt	Beautiful green and blue light . Barium bromate and cesium bromate are made, and a mix of these with sulphur is burned, giving beautiful flame colors.
*	Bi, I, Br	Bi(NO₃)₃·xH₂O HNO₃ (dilute) HCl (dilute) NaCl KBr KI	Bismuth complexes with halogens. Bismuth in its +3 oxidation state forms a black precipitate with iodide ions, and a deep orange complex is formed when excess iodide ion is present. Chloride and bromide also form complexes.
*	Br	KBr K₂Cr₂O₇ (or subst.)	Synthesis of potassium bromate. It is shown how potassium bromate can be made by means of electrolysis.
*	Br	NaBr NaHSO₄ (pH-minus) Any soluble hexavalent chromium compound	Bromine from OTC compounds. Bromine is prepared from standard swimming pool chemicals. Only a very small amount of chromate or dichromate is needed, but this can be made easily as well (no need to isolate and purify this).
*	Br, Al	Br2 Al (foil) HCl (10%) Na₂SO₃	Reaction between bromine and aluminium, spontaneous ignition of aluminium after some delay . Aluminium foil is added to some liquid bromine.
*	Br, I	NaBrO₃ NH₄NO₃ HIO₃ NH₃ (12% or better)	Ammonium halates, unstable compounds . Ammonium bromate and ammonium iodate are prepared and it is demonstrated how easily and violently they decompose on slight heating. This is a nice and fairly spectacular experiment, but it should not be scaled up.
*	Br, N	Br₂-water NH₃ (10%)	Formation of dense smoke from bromine and ammonia . Bromine vapor is poured into air, containing ammonia gas.
*	Br, N	NaBrO₃ KBr (or NaBr) NH₂OH·HCl H₂SO₄ (dilute)	Spectacular violent reaction with time delay . Hydroxylamine and bromate react violently (explosively), but not immediately after mixing. For tens of seconds nothing seems to happen and then suddenly the mix reacts extremely violently. This is a very interesting phenomenon, and it is possible to explain this behavior quite well, using a simple model.
*	Ca	CaCl₂ NaHCO₃	Explanation of what happens when hard water is heated. This experiment is a nice and safe demonstration and explanation of what happens when hard water is boiled.
*	Ca	Ca (pure metal) HCl (dilute)	Reaction between calcium and water - heat of reaction
*	Cl	KCl CsCl (optional) K₂Cr₂O₇ (optional) HCl (dilute, optional)	Tutorial for making a miniature electrolysis cell for chlorate production. This is not really an experiment, it is a description of how one can setup a nice small electrolysis cell, suitable for making chlorates from chlorides. The good working of this cell is demonstrated for making potassium chlorate and cesium chlorate.
*	Cl	NaClO₃ HCl (30%) Ca(ClO)₂·xH₂O	Colored gases - chlorine and chlorine dioxide . Chlorine gas and chlorine dioxide are made. A comparison is made of the intensity of their colors.
*	Cl	NaClO₂ HCl (30%)	Explosive properties of chlorine dioxide . The brightly colored chlorine dioxide gas is prepared and ignited. This results in a nice and quite spectacular decompositon reaction.
*	Cl	NaClO₂ HCl (≥ 25%) NH₃ (5%)	Explosion of chlorine dioxide, initiated by presence of ammonia . Another experiment, which demonstrates the danger of chlorine dioxide. This experiment shows how chlorine dioxide can be brought to explosion, simply by adding a few drops of household ammonia.
	Cl	NH₃ (5%) CuSO₄·5H₂O organic swimming pool chlorine	Funny experiments with organic swimming pool chlorine. Several funny experiments with TCCA. Smoke production, formation of strange precipitates.
*	Cl, N	N₂H₄ (dilute, 20%) HClO₄ (dilute, 20%)	Violent decomposition of hydrazine perchlorate and fairy-like sparkles. A small quantity of hydrazine perchlorate is prepared and this compound is heated, leading to a peculiar fairy-like sparkling when heating is not too strong and violent deflagration on stronger heating.
*	Cl, O	H₂O₂ (30%) swimming pool tablets	Red chemiluminiscence with chlorine swimming pool chemicals. Hydrogen peroxide is added to sodium dichloro isocyanurate or to calcium hypochlorite. A nice red chemiliminiscent light is produced.
	Cl, Br, I	Cl₂ Br₂ I₂	Colored gases from halogens. Halogens are mixed, and the interhalogen compounds formed are shown in their vapor state.
*	Cl, Br, I, N	N₂H₄.2HCl Ca(OCl)₂ NaClO₂ KClO₃ KBrO₃ KIO₃ KIO₄	Reactivity of different oxohalogenate ions. Several oxohalogenate compounds are added to a concentrated solution of hydrazine dihydrochloride. In many cases this leads to a reaction, some of them being very violent. A comparison is made of the reactivity of the different oxohalogenate ions at room temperature.
*	Cl	Cl₂ CaC₂ ("carbide")	Violent 'combustion' of acetylene in chlorine gas, explosions without need of supplying heat . Acetylene gas is bubbled into chlorine and this leads to violent explosions.
	Co	CoCl₂·6H₂O	Preparation of anhydrous cobalt(II) chloride. Careful heating of hydrated cobalt chloride produces the anhydrous compound.
*	Co, Hg	HCl (30%) HgCl₂ NH₄SCN any water soluble cobalt(II) salt	Colorful and really remarkable chemistry. In this experiment some amazing color changes can be observed. A beautiful bright red solution is prepared from which slowly very bright blue crystals are precipitated. Beautiful contrasts are produced in this experiment.
*	Cr	Cr (pure metal) HCl (30%)	Divalent chromium, extreme sensitivity to aerial oxidation. Chromium metal is dissolved in conc. hydrochloric acid with exclusion of air, and then it is shown how easily the resulting chromium(II) species are oxidized.
*	Cr	K₂Cr₂O₇ (NH₄)₂Cr₂O₇ HNO₃ (concentrated) P (red) Na₂SO₃	Synthesis and properties of polychromates. Trichromates are produced by recrystallization from conc. nitric acid. Some properties, including a spectacular decomposition reaction, are shown.
	Cr	K₂Cr₂O₇ Cr₂(SO₄)₃·12H₂O	Anhydrous chromium(III) sulfate from concentrated sulphuric acid? Concentrated sulphuric acid, with dissolved chromium compounds, is heated and a precipitate is formed.
*	Cr	K₂Cr₂O₇ H₂SO₄ (dilute) HCl (dilute) HNO₃ (dilute) CH₃CH₂OH K₂S₂O₅ (or subst.)	Reduction of dichromate - different colors of reaction product due to complex formation. Dichromate is reduced. The color of the resulting chromium(III) depends on the reductor used, and the anions, present in that solution.
*	Cr	(NH₄)₂CrO₄	Nice dendritic crystal structures. Ammonium chromate is dissolved and the solution is allowed to evaporate to dryness.
*	Cr	H₂O₂ K₂Cr₂O₇ KOH	Synthesis of potassium tetraperoxo chromate(V). A detailed description (recipe) for making the energetic compound K₃CrO₈.
*	Cr	H₂O₂ (NH₄)₂CrO₄ NH₃ (25%)	Synthesis of triammine diperoxo chromium(IV). This is a description of how to make another very energetic chromium peroxo compound. Also some properties of the prepared compound are shown.
*	Cr	K₂Cr₂O₇ HCl (≥ 25%, high purity reagent) Na₂SO₃ HCl (dilute, hardware store)	Synthesis of potassium chlorochromate(VI). The compound potassium chlorochromate(VI) can easily be prepared. In this webpage it is demonstrated how this can be done with acceptable yield. The resulting chemical compound can be kept indefinitely and may be interesting for further experiments.
	Cr	K₃CrO₈	Explosive properties of peroxo chromates. A synthesis method for this chemical is given, and its explosive properties are shown.
	Cr	K₂Cr₂O₇ H₂O₂ any mineral acid	Beautiful effects with potassium dichromate and hydrogen peroxide. Potassium dichromate crystals are sprinkled on a highly diluted acidic hydrogen peroxide solution. The effect is stunning.
*	Cr	K₂Cr₂O₇ NaF NaCl H₂SO₄ (concentrated) H₂O₂	Fun with volatile chromium - chromyl chloride . A really beautiful experiment with chromyl chloride vapor, which is poured on a very dilute acidic hydrogen peroxide solution.
*	Cr	H₂O₂ Na₂Cr₂O₇·2H₂O C₅H₅N (pyridine) Na₂SO₃ H₂SO₄	Chromium peroxo pyridine complex and its properties. A dark blue insoluble peroxo complex of chromium is made, and some further experiments are performed with this compound. This experiments shows some remarkable color combinations and the peroxo complex is remarkably stable under reducing conditions.
*	Cr	K₂Cr₂O₇ NaF NaCl H₂SO₄ (concentrated) Na₂SO₃	Volatile compounds of chromium - another colored gas . Preparation of chromyl fluoride and chromyl chloride.
*	Cr, P	K₃CrO₈ P (red) Al (powder)	Explosive mix with red phosphorus and a peroxo chromate . A remarkably powerful and sensitive explosive mix is obtained by mixing potassium tetraperoxochromate(V) and red P.
*	Cr	KCr(SO)₄·12H₂O NH₃ (5% and 12%) HCl (10%) NaOH	Chromium(III) coordination chemistry. This is a simple experiment which shows that by simple boiling an aqueous solution of chromium(III) ions forms a complex with anions present in solution by means of ligand exchange. The experiment demonstrates this effect with sulfate anions, but the effect also exists for many other anions. The ligand exchange is accompanied with a strong change of color.
*	Cr	Na₂CrO₄ or K₂CrO₄ NH₄NO₃ or (NH₄)₂SO₄ NH₃ (dilute)	Temperature-dependence of chromate/dichromate equilibrium. In this experiment it is shown that the well-known change of color from orange dichromate to yellow chromate or v.v. has a strong dependence on temperature. The color change also can be effected by heating and cooling down.
*	Cu	CuSO₄·5H₂O NH₃ (5%) NaOH Na₂SO₃ C₆H₈O₅Na (sodium L-ascorbate) Na₂S₂O₄·2H₂O	Copper redox and coordination chemistry. A series of experiments in which redox and coordination properties of copper are shown. Copper has a very rich aqueous chemistry and this set of experiments shows some of this rich chemistry.
*	Cu	CuSO₄·5H₂O KIO₄ KOH Na₂S₂O₈	Formation of a complex of copper in oxidation state +3. Copper can be oxidized to the +3 oxidation state if it is coordinated to orthoperiodate ions. This complex is stable in aqueous solution, and it has a deep red color, which is very special for copper compounds.
*	Cu	CuSO₄·5H₂O KSCN Na₂SO₃ HNO₃	Complex chemistry of copper in combination with thiocyanate. Copper exhibits an interesting chemistry when it is combined with thiocyanate ion. An intricate interplay of coordination chemistry and redox chemistry leads to many surprising compounds with nice colors.
*	Cu	CuSO₄·5H₂O HBr (48%) HCl (30%) KBr	Unexpected colors with copper(II) ions in the presence of halogenide at high concentration. Copper(II) ions form intensely colored red/purple complex ions with bromide at low pH and high concentration.
*	Cu, S	CuSO₄·5H₂O Na₂SO₃ Na₂S₂O₅ H₂SO₃ NaOH	Redox chemistry and coordination chemistry of copper(II) and sulfite at different pH. Sulfite ion and copper(II) ion can react in different ways. Coordination complexes can be formed, but they also can interact in a redox reaction. Quite remarkable compounds can be formed in these reactions. The pH of the solutions has great influence on the actual reactions occurring.
*	Cu organic	CuI KI C₅H₅N CH₃COCH₃	A fluorescent compound of copper. This is an experiment, which is not well known. The effect demonstrated in this experiment, however, is striking and it is a shame that so few people know it. A white compound is prepared which exhibits beautiful bright yellow fluorescence under black-light.
*	Cu organic	CuCO₃·Cu(OH)₂ CH₃COOH CH₂ClCOOH CCl₃COOH HCOOH CH₃CH₂COOH CH₃C(OH)HCOOH	Inductive effect demonstrated by properties of copper acetate and related complexes. In this experiment, copper acetate, but also several substituted and related compounds are prepared. Their properties are compared and a good explanation can be given by the inductive effect.
	Cu, Sr, Li	CuCl₂ (or its hydrate) SrCl₂ (or its hydrate) LiCl (or LiBr)	Colored flames with metal salts. Metals salts are mixed/dissolved in ethanol, soaked in paper and ignited.
*	Cu, Cs	CuCl₂·2H₂O CsCl HCl (30%) CoCl₂·6H₂O (optional) FeCl₃·6H₂O (optional)	Red complex of copper and chloride. A really beautiful and remarkable solid chloro complex of copper is produced. The complex has copper in oxidation state +2 and has a bright red color, which is very special for copper in oxidation state +2. A few other similar complexes of other metals are described as well through this webpage.
*	Fe	FeCl₃·6H₂O FeSO₄·7H₂O NH₃ HCl	Preparation of a compound with magnetic properties. Only very mundane chemicals and equipment are needed in this simple, but funny experiment. A precipitate of magnetite is prepared and the precipitate is drawn through a test tube by moving a strong magnet around the test tube.
*	Fe	K₃Fe(CN)₆ CH₃COOH (white vinegar) (NH₄)₃[Fe(C₂O₄)₃] instead of "ferric ammonium oxalate", "ferric ammonium citrate" can be used as well	Cyanotype, the dawn of photography. One of the oldest processes for making permanent images is demonstrated in this experiment. Using simple chemicals and tools an image (a blue print) is made from flat objects like leaves. The word 'blue print' originally stems from this process.
*	Fe, Mn, Cl	any soluble Mn salt any soluble Fe salt bleach	Oxidizing power of bleach, bringing iron and manganese to highest oxidation state. Simple household bleach is capable of oxidizing iron to its +6 oxidation state and manganese to its +7 oxidation state.
*	H, O	H₂SO₄	Electrolysis of water -- detonating gas. Water is decomposed by means of electrolysis of a dilute sulphuric acid solution. The resulting gases are mixed and the impressive explosive power of this gas mix is demonstrated.
*	Hg	HgCl₂ (or Hg(NO₃)₂) KI	Mercury iodide, change of color and complex formation. Mercury iodide is made and it is shown how its color changes immediately after its formation.
*	Hg	HgI₂ KI AgNO₃ CuCl₂·2H₂O (or sulfate) Na₂SO₃ NaCl	Multiple compounds with a beautiful color, which depends on temperature . Mercury iodide and some derived compounds have beautiful colors, but even more surprising is the reversible change of color when the temperature is changed.
	I, S	KIO₄ S	Pyrotechnic mix with purple gaseous combustion product. Potassium periodate, mixed with sulphur gives a mix, which burns without smoke, but produces a nice purple gas mix of iodine and sulphur dioxide.
	I	NaIO₄ many metal salts	Colorful precipitates with periodate ion. Many metal salts are mixed with a solution of sodium metaperiodate.
*	I	H₅IO₆ NH₃ NaOH	Preparation and properties of ammonium periodate. A simple experiment, in which ammonium (meta)periodate is made. This compound explodes when it is heated.
*	I	I₂ oleum (20% SO₃)	Formation of cationic iodine species in oleum. Iodine is dissolved in oleum and the formation of a blue cationic species is demonstrated. Iodine is brought to oxidation state +½, which is very special for iodine.
*	I	CHI₃ Na₂SO₃ CH₃COCH₃	Decomposition of iodoform. Iodoform is heated and its decomposition products are shown.
*	I, Cl	KIO₃ HCl (30%) CH₃COCH₃ H₂SO₄ H₂O₂ (3%) Na₂SO₃	Preparation of polyhalide salt of potassium. Potassium iodate is added to concentrated hydrochloric acid. Chlorine gas is formed, and needle-like crystals of potassium tetrachloroiodate(III) are formed as well. This is a remarkable polyhalide compound.
*	I, Cl	I₂ Ca(ClO)₂·xH₂O Mg HCl (dilute) Na₂SO₃	Example of interhalogen compounds . Chlorine gas is made, and this gas is lead over iodine. Iodine monochloride and iodine trichloride are formed. The monochloride is reacted with magnesium.
*	I, N	KIO₃ KH(IO₃)₂ NaNO₂	Reaction between molten nitrite and iodate, formation of beautiful wine red gas mixes.
*	I, S	KIO₄ NH₄SCN	Colored smoke -- purple and yellow. A mix of potassium periodate and ammonium thiocyanate is ignited. This gives purple smoke, which quickly turns yellow. Quite a remarkable experiment.
*	I, N	H₅IO₆ N₂H₄ alternatives based on KIO₄ and salts of hydrazine are possible	Violent reaction between hydrazine and periodate. In this experiment it is demonstrated that hydrazine and periodate react extremely violently and so much heat is produced that iodine escapes as vapor, even from aqueous solutions!
*	I, P	H₅IO₆ P (red)	Delayed self-ignition of mix of periodic acid and red phosphorus. Some red phosphorus and periodic acid are mixed. After a while, this mix suddenly self-ignites and a plume of fire and smoke is produced.
*	I	NaI NaOH Cl₂ (generated)	Synthesis of sodium orthoperiodate. Sodium orthoperiodate is prepared by leading chlorine gas through a solution of sodium iodide and sodium hydroxide. The nice thing of this synthesis is that it allows one to make periodate without needing access to any special chemicals besides the easy to obtain sodium iodide.
*	I	KIO₃ KOH Cl₂ (generated) HNO₃	Synthesis of potassium periodate. Potassium periodate is prepared by leading chlorine gas through a solution of potassium iodate and potassium hydroxide. Some acid is used to precipitate all of the periodate as the very sparingly metaperiodate.
*	Ir	"IrCl4" HCl (dilute) Na₂SO₃ Na₂S₂O₈ NH₃ (dilute)	Iridium -- goddess of the rainbow. All colors of the rainbow can be created from a single iridium compound and a few common other reagents. Iridium has a very rich redox and coordination chemistry.
*	K	KOH Mg (coarse powder) tert-butanol Aliphatic solvent, boiling around 220 C, free of aromatics	Synthesis of potassium from magnesium and potassium hydroxide . This is an interesting and also remarkable synthesis of potassium, which can be carried out at very mild conditions and which only requires reactants which are not really hard to obtain.
*	Mg, I	Mg (powder) I₂ Na₂SO₃	Water-initiated violent reaction between magnesium and iodine. Magnesium and iodine are mixed, and a violent reaction is initiated by adding some water.
*	Mn	KMnO₄ C₁₂H₂₂O₁₁ (sugar) NaOH	Chemical chameleon with permanganate. A dilute solution of potassium permanganate is reduced with an alkaline sugar solution. The solution slowly goes through many colors.
*	Mn, Ce	KBrO₃ CH₂(COOH)₂ MnSO₄·xH₂O H₂SO₄ (dilute) Ce(SO₄)₂·xH₂O	Oscillating reaction. The classical Bhelousov-Zhabotinsky reaction. A well-known classical, but very beautiful, experiment.
*	Mn	KMnO₄ H₂SO₄(concentrated) CH₃COCH₃	High speed image capturing of explosions . A drop of acetone is dripped on a mix of concentrated sulphuric acid and potassium permanganate. The resulting explosion is filmed at 60 frames per second.
*	Mn	KMnO₄ H₂SO₄(concentrated) CH₃COCH₃	Liquid from hell -- fire on first contact . This is a spectacular demonstration, very similar to the one above. Acetone, sticking to a glass rod, is put in a mix of conc. sulphuric acid and potassium permanganate.
*	Mn	KMnO₄ H₂SO₄(concentrated) CH₃CH₂OH	Miniature explosions in a test tube . Potassium permanganate is put in a test tube, containing sulphuric acid, with a layer of ethanol floating on top of the acid. This results in little flashes and crackling noise, after an induction period of a few minutes.
*	Mn	KMnO₄ NaF H₂SO₄ (concentrated) Na₂S₂O₅ (or Na₂SO₃)	A volatile compound of manganese and corrosion of glass . A volatile green compound of manganese(VII) is produced from potassium permanganate, sodium fluoride and conc. sulphuric acid.
	Mn	MnO₂ Al (powder) P (red)	Flash powder with manganese dioxide. Manganese dioxide and fine aluminium powder make a powerful flash powder. With red P it can be ignited more easily.
*	Mn	Mn (very pure 99.99%) MnCl₂ (hydrated is OK) HCl (37%, reagent grade) KMnO₄ (reagent grade) H₂O₂ (10% by weight) Na₂SO₃	Properties of manganese(II) ion at very high concentration. In this experiment it is shown that manganese(II) ions in aqueous solution are pale pink, also at very high concentration and in the presence of concentrated hydrochloric acid. This is different from what some textbooks claim, which mention the existence of green complexes.
*	Mo	MoO₃ ascorbic acid NaH₂PO₂ Na₂S₂O₈ H₂SO₄ (dilute) NaOH H₂O₂ (3% solution)	Colorful compounds of molybdenum. This experiment demonstrates the very interesting and colorful, but also rather incompletely understood chemistry of molybdenum in aqueous solution. All colors of the rainbow can be produced with molybdenum in aqueous solution.
	N	Cu HNO₃ (≥ 50 %)	Properties of nitrogen oxides, NOx. Some nitrogen dioxide is made and it is shown that the color of the gas mix strongly depends on temperature.
	N	HNO₃ (≥ 50 %) H₂SO₄ (concentrated) CH₃CH(OH)CH₃	Violence of a nitration runaway. A simple experiment, in which a copious amount of nitrogen dioxide is made in a violent reaction. Nice for demo purposes.
*	N	NaNO₂ KMnO₄ (or MnO₂) H₂O₂ (3%) HCl (10%)	Reaction in gas phase. Nitrogen monoxide and oxygen are prepared and mixed by setting up an apparatus with two glass bottles. As soon as the gases mix, a deep brown gas is formed.
*	N	N₂O CS₂	Barking dog reaction . Nitrous oxide is mixed with carbon disulfide vapor and this mix is ignited. This results in a very spectacular reaction with bright light and an impressive barking noise.
	N, C	CH₃OH NaNO₂ (or KNO₂) HCl (10%)	A fast and complete formation of an inorganic ester. Methyl nitrite is prepared in this experiment and simply is isolated, because it bubbles out of solution.
*	N, C	HNO₃ (≥ 60 %) H₂SO₄ (concentrated) NaHCO₃ cellulose wadding	Nitration of a piece of cellulose wadding . A classical experiment, in which common white cellulose wadding is nitrated. The nitrated wadding quickly burns without smoke and without leaving any residue/ashes.
	Na	Na HCl (dilute)	Dangerous experiments with sodium metal. Sodium metal is put in dilute hydrochloric acid. The heat, produced in this reaction, ignites the hydrogen, formed in this reaction. This leads to a loud bang!
	Na	phenolphtalein pH indicator	Sodium skirting over water surface. This is a very simple experiment. Some sodium is thrown in a tank, filled with water, in which some pH indicator is dissolved. This results in a nice visual effect.
*	Nb	Nb (sheet or stick) HCl (10%) NaF HNO₃ (≥ 50 %) NaOH	Coloration of metallic niobium by means of electrolysis . Niobium metal is used as anode in an electrolysis setup. The metal is covered by an oxide layer. Quantum effects give beautiful colors to the metal with thin oxide layer.
*	Nd	Nd₂O₃ H₂SO₄ (dilute) HNO₃ (dilute) HCl (dilute, colorless grade) HCl (30+ %, reagent grade)	Narrow absorption bands of neodymium ions. In this experiment it is shown that the appearance of a solution of neodymium salts strongly depends on the type of light source, used for viewing the solution. The effect is really striking!
*	Ni	Na₂S₂O₈ HNO₃ (dilute) NiSO₄·xH₂O NaOH	Very high oxidation state of nickel with persulfate. Nickel is brought to +3 or even +4 oxidation state by persulfate ion under alkaline conditions.
*	Ni	NiSO₄·xH₂O NaOH KCN H₂SO₄ (dilute) H₂O₂ ligroin (boiling 40...60 °C) bleach	Nickel in oxidation state +1. In this experiment, nickel is brought to the remarkable oxidation state +1, which is very special for this metal, which usually is in oxidation state +2 in aqueous solutions.
*	Ni, Cu	NiSO₄·xH₂O NH₂CH₂CH₂NH₂ NiNO₃.6H₂O NH₄ClO₄ H₂O₂ NiCO₃ HClO₄ (aqueous) CuO	Nickel - ethylenediamine complexes. Nickel forms differently colored complexes with ethylenediamine. These complexes have strong bright colors. The tris-complex also can be crystallized easily with different cations, most notably the perchlorate ion. The solid perchlorate is an energetic and beautifully looking compound. This webpage also contains a link to an experiment, in which the copper complex is made as perchlorate salt. This also is easily crystallized and has equally energetic properties as the nickel complex.
*	O	H₂O₂ many metal salts HCl (10%) NH₃ (5%)	Peroxo complexes of transition metals in high oxidation states. Many transition metals show colorful and sometimes remarkable peroxo complexes when they are in high oxidation states.
*	P, I	P (red) KIO₄ (or KClO₄)	High speed image capturing of explosions with purple/pink smoke . Potassium periodate and red phosphorus are mixed and the mix is ignited. This gives an explosion, with formation of a pink cloud of smoke. High-speed images are made of this reaction.
*	P, Cl	P (white) NaOH Cl₂ bleach HCl	Self-ignition of phosphine in chlorine gas . In this experiment some phosphine is prepared, some of its properties are shown, and the gas is bubbled in an atmosphere of chlorine, resulting in self-ignition of the gas and contraction of gas volume.
*	P	P (red)	Conversion of red phosphorus to white phosphorus . This is a write-up on how one can convert red phosphorus to white phosphorus. The process described here is suitable for making a few grams of white phosphorus per batch.
	P	P (red) KClO₃	Sensitivity of mix of potassium chlorate and red phosphorus. A mix of red phosphorus and potassium chlorate can be ignited, simply by lightly tapping on it with a smooth rod.
*	P, Cl, Al	P (red) Cl₂ KNO₃ Al (powder)	Miniature fireworks (bright flashes) in a test tube. A mix of aluminium powder, potassium nitrate and red phosphorus is thrown in chlorine gas. This results in a very bright white flash.
*	P	P (red) Br₂	Synthesis and isolation of phosphorus tribromide . Phosphorus tribromide is prepared by means of careful addition of red phosphorus to bromine. By means of distillation the product is purified.
*	P, Br, Cl	P (red) Br₂ Cl₂	Reaction between bromine/chlorine and phosphorus . Red phosphorus, when thrown in chlorine gas or bromine vapor, is ignited and continues burning in the gas.
*	Pb	Pb(NO₃)₂	Electrolysis, formation of lead crystals. A solution of lead nitrate in a petri dish is electrolysed. Crystals of lead metal are formed at the cathode.
	Pb, I	Pb(NO₃)₂ KI	Nice effects in petri dish with yellow precipitate. Lead nitrate and potassium iodide are put in a petri dish, filled with water. The dissolved salts diffuse towards each other, giving nice effects.
*	Pb, I	PbI₂	Lead iodide: color depending on temperature and decomposition. lead iodide is heated. If heating is not too strong, then it can change color reversibly from yellow to deep red.
*	Pb, I	Pb(CH₃COO)₃·3H₂O KI CH₃COOH (dilute)	"Golden" crystals of lead iodide. A yellow precipitate of lead iodide is made and dissolved in boiling water. On cooling down, beautiful glittering yellow crystals are formed.
*	Pr	Pr (pure metal) PrCl₃·xH₂O HCl (30%)	Praseodymium chemistry. Praseodymium is dissolved in hydrochloric acid and some experiments are done with the resulting metal salt solution.
*	Rb, I, Cl	Rb₂CO₃ HIO₃ HCl (30%)	A polyhalide compound of rubidium. Rubidium is known to form polyhalide compounds fairly easily, more so than the lighter alkali metals. In this experiment such a compound is prepared. During the preparation a beautiful crystalline precipitate is formed.
*	Re	Re (metal powder) HNO₃ (≥ 50 %) HCl Zn SnCl₂·2H₂O C₆H₈O₅Na (sodium L-ascorbate) NaOH K₂S₂O₅ NaBH₄	Rhenium chemistry. Rhenium is dissolved in concentrated nitric acid, giving a solution of perrhenic acid. This solution is used as a starting point for several redox experiments.
*	Ru	Ru (metal powder) bleach NaOH HCl (dilute) H₂SO₄ (dilute) K₂S₂O₈ Zn Na₂SO₃	Ruthenium chemistry. Ruthenium metal is dissolved in household bleach, giving a solution, containing ruthenate(VI) ion. This solution is used as a starting point for a large set of experiments, exploring the rich and colorful aqueous chemistry of this element.
*	S	S₈ C₆H₅CH₃	Recrystallization and/or refining of sulphur. Sulphur is dissolved in hot toluene and when this solution cools down, nice crystals of sulphur are formed.
	S, Cr	SOCl₂ H₂SO₄ (concentrated) K₂Cr₂O₇	Thionyl chloride and potassium dichromate, no reduction of dichromate without water. Potassium dichromate is dissolved in thionyl chloride. It is not reduced to chromium(III). With concentrated sulphuric acid and water, chromyl chloride and HCl are formed.
	Sb	Sb₂S₃ HCl (30%)	Antimony sesquisulfide, stunning change of its appearance when it is hydrated. Some pyro-grade black antimony sesquisulfide is dissolved in conc. hydrochloric acid. When the solution is diluted, then hydrolysis occurs and a bright yellow precipitate of hydrated antimony sesquisulfide is produced.
*	Se	Se HNO₃ (≥ 50 %) Zn Na₂SO₃ (or Na₂S₂O₅)	Allotropes of selenium. Gray selenium is dissolved in conc. nitric acid, giving selenous acid in solution. This solution in turn is reduced to selenium. The selenium now precipitates as the red allotrope.
*	Se	Se Na₂S.xH2O H₂SO₄ (dilute) NaOH Na₂S₂O₈ Na₂SeO₃ SeO₂ HBr (40%, 48%) Na₂SO₃	Less common aspects of selenium chemistry . The element selenium has some interesting properties in combination with sulfide and bromide. It can form strongly colored species, which are stable in aqueous solution and can be studied without the need of exotic solvents.
*	Si	SiO₂ Mg HCl (dilute)	Formation of a self-igniting gas from fine sand powder and magnesium . Magnesium metal and finely powdered sand are reacted to form magnesium silicide, which in contact with dilute acids produces self-igniting silane gas. This is a spectacular, but somewhat dangerous experiment.
*	Sn	Sn (preferably powder) I₂ CH₂Cl₂ or CS₂	Preparation of tin(IV) iodide, a volatile covalent compound. Tin and iodine are made to react in a suitable solvent for iodine. Under these conditions the interesting compound tin(IV) iodide is formed, which can easily be isolated. Some properties of this compound are shown.
*	Sn	SnCl₂·2H₂O KI HCl (dilute)	Tin chloride and iodide, formation of a remarkable orange complex/precipitate. Tin chloride and potassium iodide, when added to each other, result in formation of yellow precipitate. At high concentration and after some time, this precipitate turns orange.
*	Te Cl, Br, I	TeO₂ Na₂TeO₃ HCl (30% by weight) HBr (40% by weight) H₂SO₄ (dilute) KI Na₂SO₃	Colorful properties of halogen complexes of tellurium in oxidation state +4. At very low pH, tellurium in oxidation state +4 forms remarkable compounds with the halide ions. The heavier the halogen, the more stable the complex and the more intense the color. All of these complexes, however, are very prone to hydrolysis in aqueous solution.
*	Te, Se, S	Te Se S NaH₂PO₂·H₂O Na₂S·xH₂O K₂Cr₂O₇ H₂SO₄ (concentrated) H₂O₂ (3%) P₄O₁₀ (optional) SO₃ (20% oleum)	Poly cation species of tellurium and selenium, no similar reaction with sulphur under the same conditions. Tellurium and selenium are dissolved in hot concentrated sulphuric acid. The solutions contain remarkable cationic species with peculiar structure. Sulphur does not show such a reaction in sulphuric acid, but it does react with oleum.
*	Ti	Ti (powder, granules) HCl (30%) H₂O₂ (3%) Na₂SO₃ Na₂S₂O₈	Aqueous chemistry of titanium. Titanium is dissolved in hydrochloric acid. The resulting purple solution is used as a starting point for exploring the metal's aqueous chemistry.
*	V, P, Cl	V₂O₅ PCl₅	Volatile vanadium compound, leading to green gas and red smoke. Phosphorus pentachloride is capable of chlorinating vanadium pentoxide and the resulting compound is volatile and gives rise to formation of interesting green vapor and red smoke when it is heated.
*	V	V₂O₅ Zn (filings, granules) NaOH HCl (dilute) Na₂SO₃	Colorful oxidation states of vanadium. Vanadium pentoxide is dissolved in a solution of sodium hydroxide. This solution is acidified and then the vanadium in its +5 oxidation state is reduced, all the way down to +2 oxidation state.
*	V	V₂O₅ KOH H₂O₂ (15%) H₂SO₄ (dilute) CH₃CH₂OH (96%) P (red)	Isolation of peroxo complex of vanadium. In this experiment a peroxo complex of vanadium is made and this complex is isolated as a dry powdered solid. The isolated compound is stable on storage and has energetic properties. A mix with red phosphorus deflagrates on ignition.
*	Zn, Cu	Zn (granules or sheet) ZnO NaOH Cu (coin) dilute HNO₃ / vinegar	Zinc plating of copper coin. A copper coin is zinc plated by putting it in an alkaline solution, containing zincate ions, while at the same time the coin touches a piece of metallic zinc.

*	C, H	different chemicals for each of the different experiments	Color of the flame of burning gases. Different gases are collected in a test tube, sucked in a syringe, and then ignited. Many different flame colors can be obtained from different gases. Some flame colors are remarkable, such as pink/rose and grey.
*	physical	NaCl	Characteristics of an electrolysis cell. The voltage-current relation of an electrolysis cell is investigated in this experiment.
*	physical	NaCl	High voltage electrolysis, and creation of lightning . A strong salt solution is electrolysed, using a high voltage source and a plasma beam as anode. Some 'lightning' is produced as well.
	physical	CH₃CH₂OH CH₃OH H₃BO₃	Near-explosions of alcohol/air mixes in confined spaces. Alcohol vapor is ignited in flasks with long necks and long tubes.
	organic	CH₃NO₂ NaOH	Violent reaction between nitromethane and sodium hydroxide. Nitromethane and sodium hydroxide are mixed. After a short induction time, a very violent reaction starts.
	organic	CH₃COCH₃ styrofoam	Collapsing styrofoam. Acetone is sprinkled on a piece of styrofoam. The styrofoam literally collapses.
*	organic	HCOOH CH₃COOH NaOH	Precision electrolysis of acetate and formiate. Acetate and formiate are electrolysed and based on the observations in this experiment, the net reactions are derived. A demonstration of what can be achieved with a combination of careful observation and reasoning.
*	organic	HClO₄ NH₂CH₂CH₂NH₂ NaHCO₃	Violent decomposition of an organic perchlorate salt. A perchlorate salt of a basic organic amine is prepared and it is shown how this salt decomposes violently when it is ignited.
*	organic	red cabbage HCl (dilute, few percent) CH₃COOH (dilute) dish washing soap NH₃ (5%) Na₂CO₃ (or NaOH)	Fun with red cabbage. Red cabbage juice is treated with solutions of different pH. Surprising colors can be obtained in this way, much more than the well-known pink/rose to violet/blue colors, which one knows from the kitchen.
*	organic	phthalic anhydride m-C₆H₄(OH)₂ (resorcinol) H₂SO₄ (concentrated) NaOH	Beautiful green fluorescence -- synthesis of fluorescein. A strongly fluorescent compound is made and with a UV-LED the strong fluorescence is demonstrated in a spectacular way.
*	organic	C₁₂H₂₂O₁₁ (plain sugar) H₂SO₄ (concentrated)	Dehydration and oxidation of sugar by concentrated sulphuric acid. This is a spectacular experiment, in which sugar is charred by concentrated sulphuric acid and a lot of black foam, smoke and noise is produced.
	technical	NaBr KBrO₃ H₂SO₄ (concentrated)	Making bromine by distillation. Bromine is made in an acidic solution and this is distilled in order to obtain the pure element. It is dried with concentrated sulphuric acid.
	technical	HNO₃ (≥ 60 %) H₂SO₄ (concentrated)	Making 90% nitric acid. Ordinary concentrated nitric acid (60% or so) is transformed into very strong acid of 90+ % concentration by means of distillation.
	technical	NH₃ (dilute, 5%)	Concentrating and purification of ammonia. Ordinary household ammonia is concentrated and purified by heating the liquid, driving out the gas and leading that gas through distilled water. This process can be used to make very pure ammonia at a higher concentration than the plain household ammonia.
*	technical	KCl CsCl (optional) K₂Cr₂O₇ (optional) HCl (dilute, optional)	Tutorial for making a miniature electrolysis cell for chlorate production. This is not really an experiment, it is a description of how one can setup a nice small electrolysis cell, suitable for making chlorates from chlorides. The good working of this cell is demonstrated for making potassium chlorate and cesium chlorate.

*	N,	Si (specially processed material with I/O capabilities) HNO₃ Fe	Colorful gases with Fe, HNO₃ and GiMp_2.2.6. How the element silicon adds many colors to brown gases.

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