www.uq.edu.au school science lessons appendixa

School Science Lessons Appendix A, Chemical compounds by chemical name Updated: 2010-12-18 CH Please send comments to: [email protected]

See 7.2.2: Elements and chemical reactions | See 19.4.0 Food chemistry | E number = food additive Chemical Name Molecular formula, synonyms or similar or mineral, (notes on use)Acetic anhydride (CH3CO)2O, is highly volatile liquid with an irritating odour because acetic acid

forms by reaction with moisture in the air. Acetic anhydride is corrosive to the skin, eyes and gut, but has low toxicity because of conversion to acetic acid, a natural component of the human diet. If mixed with water, it becomes acetic acid by hydrolysis in less than 3 minutes, heat is evolved, but the reaction catalysed by the acetic acid formed is not dangerous if < 25 mL is used. Prepare acetate esters from alcohols by reaction with acetic anhydride. The reactions with water can be hazardous, with alcohols may be vigorous if acid catalysts present, with boric acid, chromium (VI) oxide, permanganate salts, nitric acid and metal peroxides may be Explosive.

Acetic acid

CH3COOH, ethanoic acid, weak acid, Ka small, colourless, mobile liquid, r.d.

glacial acetic acid, 17 M, 1.05 gm cm-3, b.p. 118oC, solidifies 16.7oC, conc. 17.5 M, dilute 6 M, miscible with water, pungent odour, "glacial" ethanoic acid, (vinegar, eisel, is about 5% acetic acid, sour wine), E260, (anti-bacterial medicine, cleaner, sanitizer, stain remover, food).

Acetone

(CH3)2C=O, CH3.CO.CH3, dimethyl ketone, 2-propanone, clear colourless volatile

liquid, characteristic smell, inflammable, r.d. 0.79 gm cm-3, b.p. 56.5oC, miscible with water and ether and oils, sharp sweet taste, characteristic odour, (solvent for resins, primers, plastics, in some nail polish removers and paint thinner, may be sold as "pure acetone"). UN CAS No 1090

Acetylene C2H2, ethyne, Use acetylene in a fume cupboard or ruse very small quantities in a well-ventilated area. Use eye and skin protection to avoid splashes. Mixtures of acetylene and air may be dangerously explosive. Also, explosive acetylides form when acetylene reacts with silver or copper (I) salts. Formerly, bicycle "carbide lamps" used calcium carbide + water --> acetylene + calcium hydroxide. However, the calcium carbide used to decompose in moist air to form the unpleasant odour of acetylene. The gas has a foul smell because of the presence of traces of phosphorus hydrides. This decomposition could be lessened by pouring petroleum over the calcium carbide to exclude air and moisture. Acetylene forms highly explosive mixtures with air, but is otherwise not toxic. As prepared from the reaction of calcium carbide with water, it usually has an evil smell because of the presence of small amounts of phospines. Do not inhale the impure gas. Handle acetylene cylinders with care. Unplanned release of a large quantity of acetylene may result in a serious fire or explosion. In acetylene cylinders, acetylene is dissolved in acetone supported on a porous diatomaceous earth base. The pressure inside an acetylene cylinder is therefore lower than in other cylinders that contain compressed gases, e.g. nitrogen.

Adipic acid Hexanedioic acid, butanedicarboxylic acid, (CH2)4(COOH)2, colourless needles, (used to make nylon 6,6 (Bri nylon), and polyester resin).

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Aluminium chloride

Hydrates, AlCl3.6H2O, anhydrous AlCl3 is covalent.

Aluminium hydroxide

Al(OH)3 solution, is amphoteric, 1. as a base, aluminium hydroxide with acids forms aluminium salts, 2. as an acid, aluminium hydroxide with bases forms aluminates, [Al(OH)4(H2O)2]-

.

Aluminium oxide

Al2O3, alumina (porcelain), amphoteric, corundum (hardness 9, abrasive, in red ruby, in blue sapphire), diamantine, emery powder, (abrasive), corroded aluminium, (bauxite, hydrated aluminium oxides Al2O3.nH2O + laterite), alumina hydrate for craft, alumina has amorphous or crystalline state in corundum and bauxite.

Aluminium potassium sulfate

Al2(SO4)3.K2(SO4).24H2O, KAl(SO4)2.12H2O, potash alum, potassium alum, kalinite, hydrated aluminium potassium sulfate, aluminium potassium sulfate 12-hydrate, alum sold at grocery shops. It is very astringent and is used for purifying water.

Aluminium sulfate

Al2(SO4)3.18H2O, wrongly "alum", E520, foam agent in fire extinguishers, water filter powder, flocculation agent, food additive E520, modifier, precipitator in sewage treatment, mordant, paper sizing, for 0.l M solution., 66 g of hydrated salt in 1 L water.

Ammonia Ammonia solution

NH3, (weak ammonia, about 10%, is sold as a household cleaner), Ammonia is an extremely irritating gas and is flammable in the presence of sufficient oxygen. Do not prepare ammonia in an open room. Use a fume cupboard. Ammonia is less dense than air. Ammonia solution is a weak electrolyte so the properties of the molecules and the ions in the solution affect its properties. Concentrated ammonia solution forms ammonia gas whenever the container holding it is opened. Ammonia is extremely irritating to the nose and lungs. If ammonia solution is spilt a fume cupboard evacuate the area until the ammonia fumes have dispersed. Do not allow ammonia solution to contact the skin. Do not add concentrated ammonia to solid iodine because a black solid, called touch powder, NI3NH3, forms. If dry, the slightest friction causes it to explode. Do not add concentrated ammonia to bleach or bleaching powder because nitrogen trichloride, NCl3, may form. This is a violently unstable liquid that may explode. Do all experiments using ammonia in a fume cupboard.

Ammonium bicarbonate

NH4HCO3, ammonium hydrogen carbonate, white crystals, crystal ammonia, in some baking powders.

Ammonium carbonate

(NH4)2CO3, sal volatile, aromatic spirits of ammonia, salt of hartshorn, ammonium sesquicarbonate, sold as "smelling salts", baker's ammonia, crystal ammonia, colourless crystals or white powder, ammonia-like odour, very soluble, decomposes in hot water, E503 (commercial ammonium carbonate is double salt NH4HCO3.NH2COONH4 that releases ammonia, in sal volatile, smelling salts).

Ammonium chloride

NH4Cl, sal ammoniac, colourless, odourless, cubic crystals or crystal mass, white granular powder, sublimes without melting, weakly hygroscopic, saline taste, (soldering flux, dry cell flux in torch battery).

Ammonium (NH4)2CrO4, yellow monoclinic crystals, decomposes at 185oC, loses ammonia

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chromate gas, alkaline solution, needs cool storage.

Ammonium dichromate (VI)

(NH4)2Cr2O7, ammonium dichromate, orange red monoclinic crystals, heat decomposes, (Not "ammonium bichromate"). The hazardous properties of this salt are similar to those of other soluble chromate and dichromate salts. Ammonium dichromate, along with other yellow chromate and orange dichromate salts is believed to be carcinogenic. An ammonium dichromate is unusual in that it undergoes an exothermic decomposition on heating to form green chromium (III) oxide, nitrogen gas and water. Start the reaction with a lighted match. The reaction continues because it is exothermic. This reaction is not dangerous if only small quantities of material are used. The reaction is dangerous if particles of undecomposed ammonium dichromate are projected into the air and inhaled. Ammonium dichromate is often used in the volcano experiment.

Ammonium iron (II) sulfate

(NH4)2SO4 FeSO4.6H2O, Fe(NH4)2(SO4)2.6H2O, ferrous ammonium sulfate, Mohr's salt, pale blue-green, monoclinic crystals or granules, in air slowly oxidizing and efflorescent, r.d. 1.86, store in dark place.

Ammonium nitrate

NH4NO3, colourless crystals, soluble in water and ethanol, nitrate of ammonia garden fertilizer, in explosives, (must not be mixed with diesel oil to make an explosive mixture).

Ammonium oxalate

(NH4COO)2.H2O, ammonium ethanedioate-1-water colourless, odourless, rhombic crystals or white granules, if heated decomposes before melting.

Ammonium persulfate

(NH4)2S2O8, Ammonium persulfate, ammonium peroxydisulfate, solutions < 25%, may be used for etching of copper and printed circuit boards. Solid dust may damage intestinal tract and cause allergy reaction. Use safety glasses.

Ammonium phosphate

(NH4)3PO4, triammonium phosphate (V)-4-water, nitrogen and phosphorus garden fertilizer.

Ammonium sulfate

(NH4)2SO4, colourless, odourless, rhombic crystals or white granules, soluble in

water but not ethanol, decomposes above 280oC, sulfate of ammonia garden fertilizer, E517, cakes when stored, mascagnite mineral.

Ammonium thiocyanate

NH4SCN, white-yellow, monoclinic, deliquescent crystals, m.p. 16oC, test for ferric iron, in fixatives and explosives.

Aniline C6H5NH2, aniline oil, phenylamine, aminobenzene, clear, oily, liquid, colourless, but darkens to brown-red, distinct odour and taste, poisonous vapour, inflammable, b.p. about 182oC, flash point about 70oC, store in dark secure bottles.

Anthraquinone Anthraquinone, C14H8O2, (9,10-dioxanthracene), light grey crystal or powder, (in plant pigments, cochineal, alizarin red), (laxative in senna pods, cascara, rhubarb) Anthraquinone-2-sulfonate, sodium anthraquinone-2-sulfonate, Harmful if ingested

Aqua regia "royal water", 1 part concentrated HNO3 (aqua fortis) + 3 parts concentrated HCl, dissolves gold the "king of metals" to form AuCl4, most other acids cannot attack gold so aqua regia is called "the acid test" of gold, dissolves platinum to form H2PtCl6

Barium carbonate BaCO3, witherite, (used for craft, barium oxide flux).

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Barium chloride-2-water

BaCl2.2H2O, barium chloride, colourless, rhombic, odourless crystals or white

granules, m.p. 925oC.

Barium chromate BaCrO4, for craft, in pyrotechnics, paint pigment, corrosion control, safety matches, with explosives as initiator.

Barium hydroxide Ba(OH)2, barium hydroxide solution, (baryta water).

Barium oxide BaO, baryta, heavy spar, flux for craft, raises refractive index in optical crown glass, cathode ray tube coating.

Barium sulfate (VI)

BaSO4, barium white, blanc-fixe, fixed white, permanent white, barytes, heavy spar, almost insoluble in water, forms heavy white precipitate, (X-ray contrast meal, soil analysis, lake paint pigments).

Borax Na2B4O7.10H2O, di-sodium tetraborate-10-water, E285, sodium tetraborate decahydrate but commercial borax partially dehydrated , di-sodium tetraborate, tynkal, colourless, mineral, white powder, odourless, monoclinic crystals or granules, r.d. 1.73, m.p. 75oC, efflorescent in dry air, melts at 75oC, anhydrous at 320oC, mildly toxic so avoid ingesting and skin contact, (buffer solutions, , fire retardant, metallurgy flux, washing powders (laundry booster), bath cleaning, fungicide, insecticide, detergent booster, preservative, but not allowed in most countries), used a lot in the furniture industry.

Boric acid

H3BO3, boracic acid, orthoboric acid, trioxyboric (III) acid, colourless, odourless,

white to transparent, triclinic crystals, m.p. about 160oC, if heated decomposes to anhydride B2O3, occurs near fumaroles, (sold in pure form as a powder as eye medicine, disinfectant, insecticide), E284.

Butanedione CH3COCOCH3, 2,3-butanedione, dimethylglyoxal, dimethyldiketone, diacetyl, biacetyl, butter flavour, creamy odour.

Butenedioic acid C4H4O4, HCOOHC:CHCOOH, (CH2)2(COOH)2, cis and trans forms Butenedioic acid, cis form: cis-butenedioic acid, maleic acid, maleinic acid, malanic acid, toxilic acid Butenedioic acid, cis form: maleic acid heated forms maleic anhydride: (-CO.C.CO-), cis-butane-1,4-dioic anhydride Butenedioic acid, trans form: fumaric acid, (fumarates), fruity taste, Food acid E297, in Fumaria officinalis, mushrooms, lichens Butenedioic acid, trans form: trans-butenedioic acid, fumaric acid, (in Krebs cycle)

Cadmium iodide CdI2, white lustrous, flaky odourless crystals becoming yellow in light and air.

Cadmium selenide

CdSe, cadmium (II) selenide, cadmoselite mineral, cadmium red, craft overglaze, "pigment red 108", transparent to infrared light.

Cadmium sulfide CdS, craft yellow overglaze, cadmium yellow, pigment yellow 35, 36, semi-conductor, in light detectors, Greenrockite, Hawleyite, insoluble in water

Calcium carbide CaC2, calcium dicarbide, "carbide", acetylenogen, Calcium carbide was used in carbide lamps in cave explorer lamps, formerly in bicycle headlamps and underground mines. Many fires and explosions resulted from these lamps and they are now rarely used. The main hazard with calcium carbide is the ignition of air / acetylene mixtures. A

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violent explosion may occur, depending on the proportions of air and acetylene. Acetylene, when undiluted with air, burns with a smoky flame. Before igniting acetylene, be sure that it is not mixed with air. Commercial calcium carbide usually contains sulfur and phosphorus compounds that react with water to form strongly smelling gaseous impurities that act as a convenient indicator for the presence of acetylene.

Calcium carbonate

CaCO3, powder, almost insoluble in water unless dissolved CO2 present, calcite, chalk, limestone, Iceland spar, marble chips, marble whiting, whiting, chalk, calc spar, precipitated chalk, pearl, coral, egg shells, whitewash, calcimine, seashells, (in antacid medicines to suppress reflux), Vienna lime, E170 firming agent food additive), heated in lime kiln to form lime CaO, powdered abalone or oyster shell used as folk medicine. (school chalk, but usually school chalk is calcium sulfate)

Calcium dihydrogen phosphate

Ca(H2PO4)2.H2O, calcium tetrahydrogen di-orthophosphate, calcium dihydrogen phosphate.

Calcium chlorideCaCl2, white granules or lumps, very hygroscopic, m.p. 772oC, (drying agent, desiccant), E509, used to form calcium metal, sold as laundry booster, road salt (de-icing agent but must be pure calcium chloride)

Calcium fluoride CaF2, fluorspar, fluorite, white crystalline solid, thermoluminescent, for craft, (source of hydrofluoric acid and fluorine, used in opal glass).

Calcium hydrogen carbonate

calcium hydrogen carbonate, calcium bicarbonate, Ca(HCO3)2, temporary hardness in water, stable in solution.

Calcium hydroxide

Ca(OH)2, powder, solution, limewater, slaked lime, hydrated lime, caustic lime, slightly soluble, (whitewash, milk of lime, garden lime), E526.

Calcium hypochlorite

Ca(OCl)OH, bleaching powder, (30% chlorine), chlorinated lime, chloride of lime, calcium oxychloride grey-white powder, irritating odour, exothermic when dissolved in water, may explode if not stored securely, (bleaching powder contains both calcium hypochlorite [calcium chlorate (I), chlorinated lime] and calcium hydroxide, water sanitizing, whitening agent, "solid chlorine" is 70% chlorine for swimming pools). Bleaching powder forms chlorine gas, which is highly irritant to the lungs. If acid is added to bleaching powder, large amounts of chlorine are produced. The mixture becomes hot and may boil violently. Do not add concentrated ammonia to bleaching powder because nitrogen trichloride, NCl3, may form. This is a violently unstable liquid, liable to explode without apparent reason. Bleaching powder is a convenient source of chlorine gas for other experiments. Add dilute hydrochloric acid from a dropping funnel to a slurry of bleaching powder and water in a conical flask fitted with a rubber stopper and gas collection system. Keep a solution of sodium hydroxide nearby to stop the reaction. Adding sodium hydroxide solution to the mixture does not pose any problems. Dispose of the waste mixture by diluting it with water and washing it down the drain.

Calcium magnesium carbonate

CaCO3MgCO3, dolomite [Also, "dolomite" is any high Mg:Ca carbonate rock.].

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Calcium nitrate Ca(NO3)2.4H2O, calcium nitrate (V)-4-water, crystals.

Calcium oxide CaO, lump, quicklime, lime, caustic lime, burnt lime, E529, thermoluminescent in oxy-hydrogen flame, limelight, for excess soil acidity, sold in building supplies shops

Calcium phosphate (V)

Ca3(PO4)2, white powder, insoluble, from apatite mineral Ca5(PO4)3(OH, F, Cl), and rock phosphate, from animal bones and teeth, (used for fertilizer, facilitate uptake of DNA into cells, "bone ash" for craft), E341 Calcium phosphates, (buffer, sequestrant), formerly "calcium orthophosphate".

Calcium sulfate (VI)

CaSO4.2H2O, powder, calcium sulfate dihydrate, gypsum, calcium hemihydrate, anhydrite mineral, (plaster of Paris, CaSO4.1/2H2O, potter's plaster, school chalk, blackboard chalk, selenite, craft modelling powder), E516, (can be shaped before setting, stain remover), alabaster, in evaporating lakes, anti-inflammatory action in human body

Graphite C, Graphite powder (1-2 micron), colloidal, in oil solution to coat pith balls to give a conducting surface, dry lubricant.

Chromic acid Chromium (VI) oxide

Chromic (VI) acid, H2CrO4, (sodium dichromate in sulfuric acid), Formerly, a glass-cleaning solution "chromic acid" was prepared by mixing a metal chromate or dichromate with concentrated acid in a chromate salt solution. However, this solution is dangerous and other glass cleaning detergent solutions should be used. Chromium (VI) oxide, forms explosive mixtures with combustibles or organic compounds and should not be used for glass cleaning.

Chromium (III) oxide

Cr2O3, chromium oxide, chromium trioxide, chromic oxide, chrome green, green chromium oxide for craft.

Citric acid

C6H8O7, CH2.COOH.HO.C.COOH.CH2COOH, colourless to white crystalline powder, odourless, translucent, orthorhombic crystals or granules, "2-hydroxy propane-1, 2, 3-tricarboxylic acid", m.p. about 100oC, slightly deliquescent in moist air, loses water of crystallization in dry air, (lemon juice), store in tight containers, Also "2-hydroxy-1,2,3-propanetricarboxylic acid", about 10% dry weight of lemons.

Cobalt (II) chloride

CoCl2.6H2O, dark red crystals, pink powder, cobalt chloride, cobaltous chloride, (test for water)

Cobalt (II) oxide CoO, cobalt oxide, cobaltous oxide, green-orange to pink solid, craft blue glaze, do not inhale.

Cobalt (II) nitrate Co(NO3)2.6H2O, cobaltous nitrate, cobalt nitrate hexahydrate, red, deliquescent,

monoclinic crystals, m.p. 50o to 60oC, in dyes and inks.

Copper (II) carbonate

CuCO3, CuCO3.Cu(OH)2.H2O, basic copper carbonate, (azurite, malachite), cupric carbonate, green precipitate, bremen blue, green verditer, craft green glaze, verdigris on copper exposed to atmosphere.

Copper (II) chloride

CuCl2, cupric chloride, brown-yellow powder, covalent, green fireworks, copper (II) chloride dihydrate CuCl2.2H2O.

Cu(NO3)2.3H2O, copper nitrate crystals, blue solid, deliquescent, anhydrous form

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Copper (II) nitrate probably covalent.

Copper (I) oxideCu2O, cuprous oxide, red copper oxide, ruby copper, cuprite, for craft, red solid, insoluble, (used to make red glass).

Copper (II) oxide CuO, black copper oxide, cupric oxide, melconite, tenorite, black solid, soluble in dilute acids, (used in craft, deep blue colour in glass).

Copper (II) sulfate

CuSO4.5H2O, copper (II) sulfate(VI)-5-water, cupric sulfate, blue, triclinic crystals, efflorescent in dry air, hold on to water of crystallization in hot dry air but anhydrous at 250oC, bluestone, blue vitriol, blue copperas, (chalcanthite mineral, CuSO4.5H2O has sweet metallic taste and is slightly poisonous), (Bordeaux mixture is copper sulfate and lime used as a fungicide), wood preservative, "Root Eater", "Bluestone" algicide, (algaecide)

Copper ferrocyanide

CU2Fe(CN)6, Hatchett's Brown dye, Traube's colloidal solution, (used to remove caesium and strontium from radioactive waste).

Devarda's alloy powder, 50% Cu, 45% Al, 5% Zn, tests for NO3-, reaction with NaOH strongly

exothermic. 1,6-Diaminohexane (COR 2280)

NH2(CH2)6,NH2, ( preferred name: hexamethylenediamine, HMDA, 5% solution in water), ethylenediamine, hexamethylene diamine, hexane-1, 6-diamine, store in refrigerator, strongly alkaline, (use < 25 mL), used to make nylon.

1,4-Dichlorobenzene

C6H4Cl2, m.p. 53oC, crystalline, p-dichlorobenzene, paradichlorobenzene, 1,4-dichlorobenzol, "dichlorobenzene", deodorizer, solid blocks deodorant in male toilets, (Substitute hexadecan-1-ol or octadecan-1-ol for melting point curve experiments.), (Use ethanol to prepare dilute solutions).

Dichloromethane

CH2Cl2, methylene chloride, methylene dichloride, Freon 30, colourless liquid, b.p.

41oC, (refrigerant, degreasing, cleaning fluid, paint remover, solvent), ozone-depleting chemical so use very small amounts, (Use ethanol as solvent for dilute solutions).

Disodium hydrogen orthophosphate (V)

Na2HPO4.12H2O, disodium orthophosphate, sodium phosphate dibasic, sodium phosphate dodecahydrate, white monoclinic or rhombic crystals or granules, r.d. 1.5, m.p. 34oC to 35oC, easily loses H2O, E339 (II).

EDTA

(HOOCCH2)2N(CH2)2N(CH2COOH)2, ethylene diamine tetra-acetic acid,

sequestering agent for metal ions, Mg2+, Ca2+

Complexing agent for most metal ions, especially Ca and Mg. Water softening and remove scale from kettles, medical removal of excess metallic ions.

EDTA disodium salt

(HOOCCH2)2N(CH2)2N(CH2COONa)2.2H2O, (0.1 M, solution + sodium azide).

Ethanol, 95%

C2H5OH, ethyl alcohol, clear, colourless, mobile liquid, volatile, inflammable, distinct odour, miscible with water and most organic solvents, rectified spirit, grain alcohol, spirit of wine, constant boiling mixture = 95.6% ethanol and 4.4% water, b.p. -78.3oC, absolute alcohol = 100% ethanol, r.d. 0.79 gm cm-3, b.p. 78.5oC, absorbs moisture from air.

Ethanediol

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Ethanediol, CH2OH.CH2OH, 1,2-dihydroxyethane, ethylene glycol, glycol, b.p.

197.5oCl, ethane-1,2 diol, car radiator antifreeze, paint and plastic solvent.

Ethyl acetate CH3COOC2H5, colour less liquid, fruity odour, b.p. 77oC, ethyl ethanoate, (medicine, lacquer solvent).

Formaldehyde solution

HCHO, CH2O (aq), gas readily soluble in water, methanal, (+10% methanol), formalin: 40% methanal solution, (disinfectant, plastics), Do not mix with HCl because carcinogenic bis(chloromethyl) ether may form, so do not dispose formaldehyde and HCl in the same sink. Formaldehyde (methanal) is highly poisonous and probably carcinogenic and should be handled with extreme care. Formaldehyde is transported and stored as a concentrated aqueous solution called formalin. When a bottle of formaldehyde is opened, a large amount of gas may be released. Do not inhale the formaldehyde gas. Do experiments with concentrated formaldehyde solutions in a fume cupboard. However, dilute formaldehyde solutions produce little formaldehyde and can be safely handled in the open laboratory. Preserve biological specimens in a solution of 50% ethanol and 50% water, instead of formaldehyde solution. Do not mix hydrochloric acid and formaldehyde solution because highly carcinogenic bis(chloromethyl) ether may form. Do not store bottles of hydrochloric acid near formaldehyde because the reaction might occur in the air. Do not dispose of formaldehyde solutions and hydrochloric acid in the same sink system.

Formic acid

HCOOH, methanoic acid, conc. 46 M, hydrogen carboxylic acid, in ants and stinging nettles, most simple carboxylic acid, Formic acid is highly poisonous and should be treated with care. It is highly volatile and the vapour should not be inhaled. Formic acid is the only simple aliphatic carboxylic acid to possess reducing properties because of the presence of a -CHO component in the molecular structure. So formic acid is both an aldehyde and a carboxylic acid. HCOOH + H2O <--> H3O+ + HCOO-, Ka = 1.8 X 10-4.

Fructose C6H12O6, D(-), fructose, laevulose, fruit sugar, pure honey, (D form, but laevorotatory, hence "L-fructose").

Fuchsine magenta dye, rosaniline hydrochloride, C20H19N3HCl, triphenylmethane dyestuff, dark green crystals in water form purple-red solution, (the colour of flowers of Fuchsia, Onagraceae), disinfectant for skin infections, stain bacteria (not "fuchsin"), basic fuchsine has variable contents including rosaniline and similar compounds, used in Schiff reagent test for aldehydes, acid fuchsine is mixture of basic fuchsine + sulfonic groups to decolorize it.

GlucoseC6H12O6, (+), glucose, D(-), glucose, anhydrous, blood sugar, glucose, (for babies), dextrose.

Glycerol

CH2OH.CHOH.CH2OH, glycerin, clear, viscous, odourless fluid, propane-123-

triol, glycerine, propane-1, 2, 3-triol, glycerin jelly, b.p. 290oC and decomposes, r.d. 1.26, absorbs water from air, miscible, soluble in water and alcohol, (in cosmetics, toothpaste, shampoo, loosens stains).

HCl, spirits of salts, muriatic acid, clear, colourless, fuming liquid, conc. 12 M, r.d. 1.18 gm cm-3, 12 mol dm-3, E507, dilute HCl 6 M, (solution of hydrogen chloride

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Hydrochloric acid

gas), distinct odour, (aqua regia: 3 vols concentrated HCl + 1 vol concentrated HNO3). Hydrochloric acid, HCl (aq). Concentrated hydrochloric acid releases hydrogen chloride gas if open to the atmosphere. This gas is highly irritant to the lungs and causes coughing. Use the concentrated gas in a fume cupboard to avoid inhalation. If a container of the concentrated acid is broken outside a fume cupboard, evacuate the area until the fumes have dissipated. Small amounts of hydrogen chloride gas are relatively harmless and a <0.1 M dilute acid has low toxicity. The human stomach forms hydrochloric acid as part of the digestive process. Concentrated hydrochloric acid is extremely damaging to the eyes. Wear a face shield when doing any pouring experiments that might result in splashing of the liquid. Avoid skin contact with hydrochloric acid. Wash any area of the body that has been in contact with hydrochloric acid with copious amounts of water. Dilution of hydrochloric acid with water does releases some heat, but not as much as sulfuric acid. Always dilute by adding acid to water, not water to acid. Do not mix hydrochloric acid with formaldehyde solution because highly carcinogenic bis(chloromethyl) ether may form. Do not store bottles of hydrochloric acid near formaldehyde because the reaction might occur in the air. Do not dispose of formaldehyde solutions and hydrochloric acid in the same sink system.

Hydrogen peroxide

H2O2, "peroxide", bleach, antiseptic, wastewater treatment for BOD, (biological oxygen demand) Hydrogen peroxide concentration 30% solution is not permitted in schools. Contact with the eyes can cause serious long-term damage. Corrosive solution can cause skin burns. Decomposition may cause oxygen pressure build-up. Tightly sealed bottles of hydrogen peroxide may explode due to a build up of pressure of oxygen gas. Forms potentially explosive compounds with ketones (acetone), alcohols (ethanol), esters, glycerine (glycerol), aniline, triethylamine and sodium carbonate. Do not mix hydrogen peroxide with powdered Mg, Zn or Al. A 3% solution is unstable. It decomposes slowly in storage to yield water and oxygen. Can decompose rapidly in the presence of catalysts. Difficult to transport because of regulations governing is transport by air, sea and land.

Iron (II) ammonium sulfate (V)

Fe(NH4SO4),2.6H2O, Mohr's salt, ferrous ammonium sulfate, ammonium iron (II) sulfate, ammonium ferrous sulfate, 0.1 M solutions used to test cations, iron (II) compounds can be oxidized by air, but acidified solutions are stable.

Iron (II) sulfate-7-water

FeSO4.7H2O, iron sulfate, hydrated ferrous sulfate, melanterite mineral, green vitriol, copperas, wood preservative, inks.

Iron (III) chloride

FeCl3, ferric chloride anhydrous, iron chloride, iron trichloride, flores martis, black-brown, catalyst, 20% solution used for printed circuit board etchant but use eye protection and gloves. FeCl3.6H2O, iron (III) chloride hexahydrate, 0.1 M electrochemistry solution harmless.

Iron (III) oxide

Fe2O3, ferric oxide, Fe2O3.3H2O, ferric sesquioxide, rust, red iron oxide, red ferric oxide, ferric oxide red, red iron oxide, haematite, magnetite, brown-red powder, yellow / brown pigment, red ochre, burnt ore, burnt ochre, jewellers rouge polish, Venetian red, crocus powder, source of iron, mixed with red clay for liver function.

Lead (II) ethanoate

Pb(CH3COO)2.3H2O, lead (II) acetate, lead acetate, m.p. 75oC, sugar of lead, white to colourless, monoclinic crystals or granules, slowly efflorescent, absorbs CO2

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from air and becomes insoluble, test paper for H2S.

Lead (II) carbonate

PbCO3, cerussite, basic lead carbonate, (PbCO3 + Pb(OH)2), white lead, (basic lead carbonate), white lead flux, paint pigment.

Lead (II) nitrate

Pb(NO3)2, lead nitrate, white to colourless, translucent cubic or monoclinic

crystals, decomposes at 470oC, only common soluble lead compound, forms explosive mixture with combustible materials, e.g. S, P, metal powders, heated solid forms highly toxic nitrogen dioxide, test for anions: forms bright yellow precipitate of lead iodide with sodium or potassium iodide.

Lead (II) oxide, mono

PbO, yellow lead oxide, litharge, flux, lead monoxide, lead protoxide, massicott, yellow amorphous powder, fused and crystalline form called litharge used as pigment in glass and enamels.

Lead (IV) oxidePbO2, lead dioxide, car battery plates, lead-acid accumulator, (+ve accumulator electrode).

Lead (II/IV) oxide

Pb3O4, (2PbO.PbO2), dilead (II) lead (IV) oxide, lead tetroxide, trileadtetroxide, triplumbic tetroxide, massicot, red lead, minium, red lead oxide, (anticorrosive paint pigment, flux, for craft) Reacts violently with Al and Mg powders and some organic materials. Do not heat on a charcoal block. Old paints may contain > 30% lead but nowadays may contain < 1% lead.

Magnesium carbonate

3MgCO3.Mg(OH)2.3H2O, magnesium carbonate basic, light powder, magnesite, (carbonate of magnesia for craft), [food additive E504, drying agent (desiccant) and anti-caking agent in table salt], (a mild laxative and Antacid medicine), heat resistant products, dolomite MgCO3.CaCO3.

Magnesium chloride

MgCl2, magnesium chloride anhydrous, magnesium dichloride, Magnesium chloride hexahydrate, MgCl2.6H2O, magnesium chloride crystals, (hygroscopic), E511, electrolysed to form magnesium metal.

Magnesium hydroxide

Mg(OH)2, Harmful, irritates eyes and skin, brucite, weak solubility so weak base, absorbs carbon dioxide from the air in presence of water, (hydrated form called milk of magnesia, a laxative and Antacid medicine), E528.

Magnesium nitrate

Mg(NO3)2.6H2O, magnesium nitrate hexahydrate, AAS Solution, oxidizing (OXD 1474), explosive mixtures with organic compounds and combustible materials.

Magnesium oxide MgO, magnesium oxide, light powder, magnesite, magnesia, native magnesia, periclase (Antacid medicine), E530, thermoluminescent

Magnesium sulfate

MgSO4.7H2O, hydrated magnesium sulfate heptahydrate, Epsom salts, epsomite, kieserite, colourless to white, odourless, rhombic crystals or granules, loses water of crystallization to dry air and possibly microwaves and even sound waves to form green powder hexahydrate MgSO4.6H2O, anhydrous at 250oC, bitter salt, (laxative medicine, unshrinking woollen clothing, fire-proofing), crystal gardens experiments, test for Ba and Sn cations.

Manganese (IV) oxide

MnO2, manganese dioxide, manganese black, in pyrolusite, (depolarizer in dry cells, glass, catalyst, oxidizing agent). Use as catalyst for decomposition of hydrogen peroxide. Do NOT use for thermal decomposition of potassium chlorate. Hydrated manganese oxide in some medicines for schizophrenics and diabetics.

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Mercury (I) chloride

Hg2Cl2, calomel, mercury (I) chloride, horn quicksilver, Hg2Cl2, (mercurous

chloride, HgCl), white crystals, r.d. 7.15, sublimes at 400oC, (reference electrode in calomel electric cells, mercury electrode in potassium chloride solution + calomel), Calomel is found with cinnabar.

Mercury (I) nitrate

Forms explosive mixtures with combustible materials and organic compounds. The pure chemical has low toxicity if ingested. Used in redox reactions and metal displacement reactions. Millon's reagent contains mercury (I) nitrate, mercurous nitrate, in nitrous acid. Mercury (I) nitrate was formerly used in the manufacture of felt hats, caused tremors in the workers and leading to the term "mad as a hatter", a character in "Alice in Wonderland" by Lewis Carroll.

Mercury (II) nitrate

Highly toxic if ingested or absorbed through the skin, cumulative poison. Use eye and skin protection when splashes can occur. Forms explosive mixtures with combustible materials and organic compounds. Do not heat the solid because mercury vapour and nitrogen dioxide forms. Do not add ethanol to solutions of mercury (II) nitrate in nitric acid because highly-explosive mercury fulminate forms. Do not use for redox reactions. Use < 5 mL of 0.1 M per activity.

Mercury (II) chloride

HgCl2, mercuric chloride, mercury bichloride, mercury sublimate, corrosive sublimate, white crystalline solid, colourless, odourless, rhombic crystals or granules, r.d. 5.4, m.p. 277oC, solution is poisonous and very dangerous because the solution looks like water, should NOT be in the school laboratory, formerly used to treat syphilis

Mercury (II) fulminate

HG(CNO),2.1/2H2O, in cartridge detonators and percussion caps.

Mercury (II) oxide

HgO, mercuric oxide, yellow to orange, dense, odourless powder, r.d. 11.14, decomposed by light, yellow oxide of mercury or red oxide of mercury, store in dark bottles, do not heat to form oxygen gas because highly toxic mercury vapour forms. Mixture with powdered sulfur is explosive.

Methanol CH3OH, methyl alcohol, wood alcohol, clear liquid, distinct odour, volatile, flammable, poisonous, methanol and illegal home-made alcoholic beverages may cause blindness. Use < 5 mL of 0.1 M per activity or use in a fume cupboard. Substitute ethanol or methylated spirits as alternative solvent.

2-methoxyethanol Methyl cellosolve, ethylene glycolmonomethyl ether, Use in a fume cupboard o use <50 mL or g in a well-ventilated area. May cause long-term nerve damage. May be teratogenic.

Methylated spirit

C2H5OH, ( 95% CH3CH2OH, 5% CH3OH), methylated ethanol, "spirits", methylated spirits sold retail in Australia as 95% ethanol, UN 1170, duplicator fluid / spirit, Fordigraph spirit duplicator fluid, spirit vini meth, (90% ethanol + 5% v/v methanol, wood alcohol + 5% water), denatured alcohol, denatured spirits, (+ 2% of methyl alcohol, pyridine, + other coal-tar unpalatable chemicals, (in UK ethanol + 9.5% methanol + 0.5% pyridine and a blue dye). The additional substances "denature" the ethanol so it cannot be consumed. Use in illegal home-made alcoholic beverages may cause blindness. If swallowed do NOT induce vomiting because it may enter the lungs. Methylated spirit is highly flammable and must not be used near naked flames, e.g. boiled in a beaker set on wire gauze over a Bunsen burner to extract chlorophyll from leaves. Do not heat methylated spirit

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Methylated spirits over a Bunsen burner, even in a closed container such as a flask with a reflux condenser because the flask may crack. Methylated spirit burns with a nearly colourless flame so if there is a fire, be careful of the invisible flames. Use a carbon dioxide fire extinguisher and fire blankets to smother the flames. Instead, use a water bath to heat methylated spirit in a flask. Even if the flask cracks, a mixture of water and methylated spirit is much less flammable than pure methylated spirit. Repeated contact of the skin with methylated spirit can cause dermatitis so wear rubber gloves if using methylated spirit as a solvent for cleaning. Do not mix methylated spirit with an oxidizing acid, e.g. concentrated nitric acid, because a vigorous reaction or explosion may occur. Use methylated spirit as a cheap low toxicity solvent for solvent extraction. Observe the rapid changes in colour during the dissolution of plant pigments in methylated spirit

Monosodium glutamate, MSG

C5H8NNaO4.H2O, HOOCCH(NH2),CH2CH2COONa, sodium hydrogen glutamate, white crystals, soluble in water, flavour enhancer especially for Chinese food but some people allergic, formerly from seaweed Laminaria japonica.

Nessler's reagent potassium tetraiodomercurate, not permitted in some school systems because it contains mercury, Nessler's solution (Julius Nessler 1827-1905) is a solution of mercury (II) iodide in potassium iodide made alkaline with sodium hydroxide or potassium hydroxide, K2HgI4, in caustic soda solution. Add reagent to original solution. A brown colour or precipitate indicates the presence of ammonium ion. The test is very sensitive. A trace of ammonia give a yellow colour but larger amounts of ammonia give a brown colour or precipitate. The test solution must contain no NH4

+ added during analysis.

NicotineC10H14N2, pyridine alkaloid, colourless, poisonous and addictive, in tobacco leaves.

Nitrobenzene C6H5NO2, mononitrobenzene, pale yellow, oily liquid, unpleasant almond odour,

poisonous, r.d. 1.2, b.p. 211oC. Highly toxic by all routes of exposure, possibly carcinogenic. Avoid inhaling vapour and skin contact so use small quantities < 25 mL or g in a well-ventilated area. May be explosive when heated. A solution / mixture < 0.1% is not hazardous.

Oleic acidC17H33COOH, CH3(CH2)7CHCH(CH2)7COOH, octadec-8-enoic acid, colourless

viscous liquid, red oil, m.p. 14oC.

Oxalic acid (COOH)2.2H2O, ethanedioic acid-2-water, acid of sugar, colourless, white,

odourless, monoclinic crystals or granules, r.d. 1.62, m.p. 101oC - 102oC, sublimes easily above 100oC, decomposed by heat, (in rhubarb and many plants).

Pentan-1-ol CH3(CH2)3CH2OH, n-pentyl alcohol, n-amyl alcohol.

Phosphorus pentoxide

P4O10, phosphorus (V) oxide, white powder, hexagonal crystals, deliquescent, thermoluminescent. Reacts violently with water to form phosphoric acid, liberating a large amount of heat, reacts violently with iodides. With sodium and potassium metals ignition on contact. With formic acid forms highly toxic carbon monoxide gas.. Used as a dehydrating agent. The crust on the surface of old samples is mostly phosphoric acid, but remove it before using the phosphorus pentoxide beneath.

H3PO4, orthophosphoric acid, phosphoric (V) acid, orthophosphoric acid, as

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Phosphoric acid solution is colourless, odourless liquid, conc. 14.7.M, r.d. 1.71 to 1.75, miscible with water and ethanol, "Kill-rust", E33, weak acid, or white rhombic solid, 85% W /W, 90% W / W.

Potassium bromide

KBr, potassium bromide, colourless, white, cubic crystals or granules, r.d. 2.75, m.p. 730oC, (photography, formerly a sedative), used to prepare bromine water, For 0.1 M solution., 12 g in 1 L water

Potassium carbonate

K2CO3 anhydrous, "potash", (pearl-ash, commercial potassium carbonate), salt of tartar, white, odourless granules, anhydrous potassium carbonate, r.d. 2.29, m.p. 891oC, (anhydrous is hygroscopic, cakes in moist air), E501, strong alkaline solution, For 0.1 M solution., 13.8 g in water, (soap-making, glass-making, sourdough)

Potassium chlorate

KClO3, potassium chlorate (V) potassium perchlorate, Berthollet's salt, colourless,

white, odourless, monoclinic crystals, r.d. 2.32, m.p. 368oC then decomposes, explodes in contact with sulfur compounds, (in explosives, fireworks and weed killers), Do not use potassium chlorate to prepare oxygen with manganese dioxide catalyst.

Potassium chloride

KCl, sylvite, (sylvine), mineral, muriate of potash fertilizer, white, odourless, cubic crystals or powder, slightly hygroscopic, diet salt substitute, E508, extracted from waters of Dead Sea, sold as "lite salt"

Potassium chromate

K2CrO4, lemon-yellow crystals, m.p. 975oC, alkaline aqueous solution. Potassium chromate, as with other chromium (VI) salts, may be carcinogenic so handle it with care. However, when used in dilute solution, near neutral pH, it is relatively safe. When mixed with acid, chromate ions, CrO4

2-, first form dichromate ions, Cr2O72-,

then chromic acid, H2CrO4. Solutions containing chromic acid are powerfully oxidizing and highly corrosive. Do not use the cleaning mixture called “chromic acid”, prepared by dissolving a metal chromate or dichromate in concentrated sulfuric acid. This cleaning mixture is not permitted in schools because it is dangerously corrosive to skin and eyes and is probably no more effective as a cleaning agent than strong detergent solutions or a suitable solvent. Reactions of potassium chromate and dichromate with sulfur, carbon, magnesium, aluminium and phosphorus are dangerous and are not permitted in schools.

Potassium dichromate

K2Cr2O7, potassium bichromate, red prussiate of potash, ferro prussiate, bichrome,

orange to red, odourless, monoclinic crystals or granules, r.d. 2.69, m.p. 398oC, strong oxidizing agent, toxic and fire risk from oxidation, formerly used mixed with sulfuric acid to to clean laboratory glassware but nowadays this procedure not permitted in schools. Oxidation reactions involve the reduction of solutions of chromate or dichromate ions that cause colour changes from yellow or orange to pale green or colourless solutions. The reactions with the formation of an insoluble metal chromate give brightly coloured precipitates. Do not attempt to isolate these precipitates because they are carcinogenic. Prepare these precipitates in the smallest quantities that allow them to be seen. Do not use potassium dichromate solution to colour water for demonstrations. Used in machines to breath test for alcohol.

Potassium

K3Fe(CN)6.3H2O, potassium hexacyano ferrate (III), potassium ferric cyanide, ruby red, monoclinic crystals, heat decomposes then melts, r.d. 1.89, case-hardening agent, forms good crystals, used in redox experiments, Prussian blue dye,

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ferricyanide chemical analysis uses characteristic colour reactions, heating with concentrated sulfuric acid forms carbon monoxide gas, ( in dyeing, etching blueprint paper, fertilizer), Highly toxic, boiling with dilute acids forms cyanide gas, Highly toxic, with concentrated ammonia solution may explode.

Potassium ferrocyanide

K4Fe(CN)6.3H2O, potassium hexacyanoferrate (II)-3-water, coordination compound, yellow prussiate of soda, yellow prussiate of potash, prussiate of potassium, yellow monoclinic crystals or powder, r.d. 1.85, case hardening agent, used to detect Fe3+ ions, efflorescent, anhydrous at 100oC, Environmental danger, direct heating of the solid forms cyanogen gas, Highly toxic, heating with concentrated sulfuric acid forms carbon monoxide gas, Highly toxic, boiling with dilute acids forms cyanide gas, Highly toxic, Mixtures with nitrite salts are explosive.

Potassium hydroxide

KOH, "caustic potash", lye, potassa, white pellets, KOH "sticks" or rods in water, lumps, flakes, sticks, very deliquescent, absorbs CO2 and SO2 from air better than sodium hydroxide because more soluble, used to prepare soft soap and alkaline storage cells, heat from dissolving in water, r.d. 2.044, m.p. 380oC, E525, potassium lye, damages eyes and body tissues. KOH, solid, flake, pellets, 1 M analytical reagent, caustic potash, Potassium hydroxide, as a solid or concentrated solution is extremely corrosive to the skin and eyes. Always wear safety glasses when handling potassium hydroxide, even with dilute concentrations. If potassium hydroxide enters the eye, rinse the eye instantly with water. Solutions of potassium hydroxide on the skin feel soapy because fats in the skin are broken down to form anions of fatty acids, e.g. stearate, palmitate and oleate, that give the solution a slippery feel. When potassium hydroxide dissolves in water, a large amount of heat is released, sometimes causing the solution to boil violently if it has not been stirred. So, always stir solutions in which potassium hydroxide is dissolving to dissipate heat and to provide a uniform concentration throughout the solution. Potassium hydroxide solutions boil at a higher temperature than pure water. Hygroscopic so keep in sealed plastic container, More corrosive to eyes than acids,

Potassium hydrogen carbonate

KHCO3, potassium bicarbonate, (impure potassium bicarbonate "American saleratus"), colourless, odourless, white granules, r.d. 2.17, (used in buffers, baking powder, aerated waters, antacid medicines, carbon dioxide fire extinguishers, some detergents, laboratory reagent), occurs as calcinite.

Potassium hydrogen phosphate

K2HPO4, di-potassium hydrogen phosphate (V), di-potassium monohydrogen phosphate, di-potassium hydrogen orthophosphate, food additive, buffering agent, culture nutrient

Potassium hydrogen tartrate

HOOC(CHOH)2COOK, (KHC4H4O7), cream of tartar, tartar, (beeswing), acid potassium tartrate, potassium bitartrate, white crystalline acid salt, purified form of brown crystals argol, (used in baking powder, from deposits in wine vats, the "crust" in crusted port that has finally fermented in the bottle).

Potassium iodate (V)

KIO3, potassium iodate, white, monoclinic crystals or granules, slightly

deliquescent, r.d. 3.89, m.p. 560oC, oxidizing agent, (ingredient of iodized "table salt", analytical reagent), store out of light, ( potassium iodate is potassium salt of iodic acid), May ignite with combustibles or organic compounds and produce toxic fumes. Violent reaction with aluminium, magnesium, carbon, sulfur, phosphorus.

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Violent reaction with sodium bisulfite if water added. Forms toxic fumes with concentrated sulfuric acid.

Potassium iodide

KI, colourless solution, white crystals or granules, r.d. 3.12, m.p. 698oC, slightly deliquescent in moist air, bitter taste, can be separated form potassium iodate by fractional crystallization, becomes yellow when iodine lost to air, (chemical analysis, photography, additive to prepare iodized "table salt" to iodine deficiency, e.g. goitre), (in tincture of iodine medicine, solvent for iodine to form the brown triiodide ion I3

-, KI3 (aq), used as a test for starch). Detects presence of Pb2+ ions when yellow precipitate of lead iodide forms. If KI solutions become yellow from iodine formation add sodium hydrogen sulfite solution to make solution colourless again.

Potassium monoxide

K2O, "potash", K2O in fertilizer.

Potassium permanganate

KMnO4, potassium manganate (VII) (OXD 1490), Condy’s crystals, 0.2 M, 0.02 M, analytical reagent, purple-red crystals, dark purple, bronze with metallic sheen, odourless, rhombic crystals, r.d. 2.7, heat decomposes, distinct sweet bitter taste, common strong oxidizing agent and disinfectant, chemistry analytical reagent, MnO4

- ion. Potassium permanganate is a powerful oxidizing agent which forms dangerously combustible or even explosive mixtures with oxidizable materials or combustible materials: red phosphorus, cyanides, thiosulfates acetates, sugar, charcoal, sulfur, phosphorus, ammonium salts, active metal powders, organic compounds. The solid is also spontaneously flammable on contact with glycerine, ethylene glycol and other organic compounds. It forms violently explosive manganese heptoxide on mixing with concentrated sulfuric acid. Oxygen gas is formed on heating the solid, but toxic fine particles of manganese oxides are produced simultaneously; if the reaction is carried out in a test tube, place a plug of glass wool in the end of the tube to trap particles. Do not use sulfuric acid for drying oxygen gas from decomposition of potassium permanganate, since the acid could accidentally mix with the salt and react explosively. For preparing oxygen gas, it is safer to use hydrogen peroxide and potassium permanganate, or hydrogen peroxide with manganese dioxide catalyst. If potassium permanganate is used for preparation of chlorine gas by reaction with hydrochloric acid, be sure that the solid is covered with a layer of water and that hydrochloric acid is used, NOT sulfuric acid. Acidified solutions are used as an oxidant in organic chemistry for the oxidation of aldehydes or alcohols. Neutral solutions are used to distinguish between alkanes and alkenes. Dilute aqueous solutions of potassium permanganate are relatively harmless and have been used medicinally for mouth-washes and bactericides.

Potassium nitrate

KNO3, "saltpetre", "saltpeter", (occurs as nitre, niter, Bengali saltpetre), colourless,

odourless, trigonal or rhombic crystals or white granules, r.d. 2.11, m.p. 333oC, Preservative E252, strong oxidizing agent that decomposes at 400oC to lose O2, (nitrate of potash fertilizer, fireworks, food preservative, explosives, e.g. gunpowder), E252. Potassium nitrate is a powerful oxidizing agent and forms explosive mixtures with most combustible materials. Potassium nitrate has relatively low toxicity, and can be safely used in aqueous solution. Do not mix potassium nitrate with charcoal, sulfur, red phosphorus or active metals, e.g. Na,

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powdered Al, Mg, cyanides, sulfides, thiosulfates, ammonium salts, acetates, household sugar or combustible material because these mixtures may be are explosive. The demonstration of explosives is not permitted in schools. If testing production of oxygen from heated solid and lighted splint is accidentally dropped into molten salt, explosion may occur. Gunpowder, (black powder, black gunpowder), a mixture of of potassium nitrate, charcoal and sulfur, the explosive propellant formerly used in forearms now superseded for modern firearms by by smokeless powder, a mixture of potassium salts.

Potassium nitrite

KNO2, white to yellow deliquescent solid, m.p. 440oC, explodes above 600oC, used to detect presence of amino groups inorganic compounds, reacts with acids to form toxic nitrogen dioxide gas that reacts with oxygen in the air to form highly toxic nitrogen dioxide gas.

Potassium sodium tartrate-4-water

KNaC4H4O6.4H2O, double salt sodium potassium tartrate, potassium sodium tartrate, potassium sodium 2, 3-dihydroxybutanedioate, Rochelle salt, Seignette's salt, Seidlitz powder, saline cooling taste, piezoelectric.

Potassium sulfate K2SO4, sulfate of potash fertilizer, E515, white crystalline powder, prepared with potassium carbonate or potassium hydroxide with sulfuric acid, fertilizer as source of potassium iron instead of KCl for chlorine-sensitive plants.

Potassium sulfide K2S, liver of sulfur, sulfurated potash, red-yellow to brown-red, deliquescent, analytical reagent and epilatory, (depilatory), dusts may explode.

Potassium thiocyanate

KCNS, colourless prisms, r.d. 1.89, m.p. about 173oC, deliquescent

Resorcinol C6H4(OH)2, crystals, resorcin, benzene-1-3-diol, 1, 3 benzenediol, (turns red in light), (a dihydroxy phenol), (antiseptic).

Salicyclic acid HOC6H4COOH, 1-hydroxybenzoic acid, crystals, used to make aspirin, acetylsalicylic acid, an antithrombic, anti-platelet and pain relieving medicine.

Schiff reagent Mixture of fuchsine and sodium bisulfite or sulfurous acid to decolorize it that forms red-violet (magenta-purple) colour in unknown solution as test for aldehydes, called "Schiff's test".

Silica

SiO2, silicon (IV) oxide, silicon oxide, silicon dioxide, E551, quartz sand, (Silica gel desiccant is hygroscopic amorphous hydrated silica + CoCl2, self-indicating moisture test, e.g. "Tell-Tale"), powder used a non-reactive bulking material in medical tablets.

Silver bromide silver (I) bromide, Ag Br, yellow solid, dissolves in concentrated ammonia solution, (photography emulsions).

Silver chloride silver (I) chloride, AgCl, white solid, cerargyrite, horn silver, kerargyrite, occurs in silver veins, dissolves in ammonia solution, (photography emulsions, pottery glaze), expensive!

Silver iodide silver (I) iodide, AgI, not dissolve in ammonia solution, yellow solid, crystals similar to ice so used in cloud seeding.

AgNO3, large, odourless, transparent, rhombic crystals or small white crystals,

lunar caustic sticks for cauterizing, r.d. 4.35, m.p. 212oC, water-soluble, becomes dark with organic matter, test for halogens, store in dark-coloured dropping bottle

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Silver nitrate

in a cool dark place. Use Tollen's reagent to demonstrate the reduction of silver nitrate solution by formic acid to form a mirror on the inside of the test-tube. Forms explosive mixtures with combustibles, e.g. sulfur, phosphorus, ethanol, metal powders. Used in redox reactions, metal displacement reactions, testing for chloride ions, preparation of Tollen's reagent.

Soda lime

Tests for CO2, (if off-white: active, if violet: exhausted), For anaesthetics, the pH indicator ethyl violet is added to tell whether the soda lime can still absorb carbon dioxide. The critical pH is 10.3. It turns from colourless to violet. It is a mixture of sodium hydroxide and calcium hydroxide prepared by dissolving calcium oxide with sodium hydroxide solution.

Sodium benzoate C6H5COONa, sodium benzenecarboxylate, food preservative against yeast and bacteria but may cause cirrhosis, damage DNA and and increase ageing, effective pH 2.5 to 4.2, dyes, antiseptic.

Sodium bisulfite Na2S2O5, crystals, sodium metabisulfite, sodium pyrosulfite, beer-making and wine-making kits for the home.

Sodium carbonate

Na2CO3.10H2O sodium carbonate decahydrate, washing soda, sodium carbonate crystals, soda crystals, soda ash, sal soda, crystal carbonate, black ash, trona, E500 white, odourless powder, hygroscopic, soluble in water to form alkaline solution, not decomposed by heat, (also anhydrous sodium carbonate, soda ash anhydrous, Na2CO3, soda ash is commercial sodium carbonate), r.d. 2.53, m.p. 851oC , glass production, softens "hard" water.

Sodium chlorate NaClO3, white solid, crystalline, bleach, weed killer, Oxidizing (OXD 1495), Forms violently explosive mixtures with combustibles, organic compounds, ammonium compounds, sulfur, sulfides and finely divided metals, that may detonate as a result of friction, contact with strong acids by ignition. Sodium chlorate with concentrated sulfuric acid forms chlorine dioxide gas, unstable. Wood soaked in sodium chlorate become explosive.

Sodium chloride NaCl, white, cubic crystals, (colourless if large), or granules, r.d. 2.17, m.p. 804oC, common salt, table salt, sodium chloride technical grade, rock salt, halite mineral, sea salt, brine, salt chlorinating of swimming pools, animals lick natural salt or artificial blocks of salt from a salt lick, not hygroscopic if pure, for flavouring and food preservative, essential in diet, high intake cause of high blood pressure, stroke, heart disease but supplement needed after excessive dehydration and sweating, for chemistry experiments use "uniodised" table salt

Sodium citrateNa3C6H5O7.2H2O, basic, crystalline, trisodium citrate, trisodium-2-hydroxypropane-1, 2, 3-tricarboxy, (food buffer), E331.

Sodium dihydrogen phosphate (V)

NaH2PO4, sodium dihydrogen orthophosphate, monosodium orthophosphate, also monohydrate NaH2PO4.H2O and dihydrate NaH2PO4.2H2O, white, odourless,

rhombic crystals, insoluble in alcohol, slightly deliquescent, anhydrous at 100oC, in baking powder, food additive, buffers, E339.

NaHCO3, sodium bicarbonate, baking soda, bicarbonate of soda, bicarb, bicarb soda, soda, carb soda, soda lye, (saleratus, "aerated salt", "Dwight's saleratus"), white, odourless monoclinic crystals or granules, alkaline salt, r.d. 2.16 - 2.22,

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Sodium hydrogen carbonate

(occurs naturally in soda lakes, soda beds), decomposes to lose CO2, forms sodium

carbonate above 50oC, (penetrates stains and dissolves grease), (leavening agent used in: antacids, baking powders, bath salts, burn treatment, cow and cattle feed, degreasers, denture cleaning, deodorizers, fire extinguishers, general cleaners, general neutralizers, kitchen and bathroom cleaners, paint stripping, self-raising flour, soils contaminated with PCBs, toothpaste).

Sodium hydrogen sulfate

anhydrous, NaHSO4, nitre cake, sodium bisulfate, swimming pool acid, (COR 1821), Sodium hydrogen sulfate monohydrate, NaHSO4.H2O, deliquescent.

Sodium hydrogen sulfite

NaHSO3, sodium bisulfite, deliquescent, white solid but dissolves in water to form yellow solution, with heat decomposed to form sodium sulfate, sulfur dioxide and sulfur so is used to sterilize wine casks and other containers in brewing industry. If KI solutions become yellow from iodine formation, add sodium hydrogen sulfite solution to make solution colourless again.

Sodium hydroxide

NaOH, solid, white rods, pellets, pearl, flakes, lumps, granules, very hygroscopic and absorbs CO2 from air, r.d. 2.13, m.p. about 318oC, caustic soda, soda, soda lye, white caustic, caustic drain cleaner 5% caustic soda, E524 (emulsifier), 1.22 gm cm-3, cakes if stored for long period, a caustic alkali, pH solution >10, soap making, rayon and paper industry, (used in experiments for reaction of oxides of period 3 elements and analytical reagent, preparing soap and making paper), very dangerous to eyes, release heat when dissolved in water, must be pure white colour to be pure sodium hydroxide.

Sodium hypochlorite

NaOCl (aq), sodium chlorate (I), domestic bleach, oxidizing agent, 12.5% solution, chlorox, liquid bleach, colourless, strong odour, heat decomposes, (4% Cl2),

solution, (store below 25oC), (household bleach, domestic bleach, 5% NaOCl, bleaching fluid), chlorine water, chloride of soda, chlorine bleach, water treatment of swimming pools. NaOCl (aq) bleach evolves chlorine gas, which is highly irritant to the lungs. If acid is added to bleach, large amounts of chlorine are produced. The mixture becomes hot and may boil violently. Do not add concentrated ammonia to bleach. Under some circumstances, nitrogen trichloride (NCl3) forms. This is a violently unstable liquid, liable to explode without apparent reason. NaOCl can bleach materials like flower petals, leaves and human hair. NaOCl is a good source of chlorine gas for other experiments. Add dilute hydrochloric acid from a dropping funnel to bleach solution in a conical flask fitted with a rubber stopper and gas collection system. Keep sodium hydroxide solution nearby to stop the reaction.

Sodium nitrate

NaNO3, sodium nitrate (V), nitrate of soda, soda nitre, Chile saltpetre, nitratine, saltpetre, E251 (meat preservative, colour fixative), colourless, odourless, transparent, trigonal crystals or white granules, r.d. 2.26, m.p. 308oC, deliquescent in moist air, Chile saltpetre from caliche deposits, Chile nitre, (agricultural fertilizer), E251.

Sodium nitrite

NaNO2, sodium nitrate (III) white to yellow rhombic crystals or granules, r.d. 2.17,

m.p. 271oC, hygroscopic granules, (inhibits corrosion), E250. Sodium nitrite with acids forms nitrogen dioxide gas, toxic. Sodium nitrite with phenol, ammonium salts, thiosulfates, cyanides forms explosive explosive mixtures.

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Sodium perborate Strong oxidizing agent, for non-chlorine bleach detergents, monohydrate NaBO3.H2O, tetrahydrate salt crystals NaBO3.4H2O (algaecide in swimming pools).

Sodium silicate (Na2O 8.6%, SiO2 28%), solution, waterglass, water glass, soluble glass, egg preservative, fireproofing.

Sodium sulfate

Na2SO4.10H2O, sodium sulfate decahydrate, mirabilite mineral, hydrated, crystals, Glauber's salt, sal mirabile, cake, mirabilite, mirabilitum, purgative medicine, E514, (Sodium sulfate anhydrous Na2SO4, white hygroscopic powder, r.d. 2.67, m.p.

888oC), (glauberite mineral, Na2Ca(SO4)2, has a bitter and salty taste).

Sodium sulfite Na2SO3.7H2O, hydrated, sodium sulfate (IV)-7-water, E221, (Sodium sulfite anhydrous, Na2SO3, white hexagonal crystals or powder, r.d. 2.63, alkaline in water).

Sodium thiosulfate-5-water

Na2S2O3.5H2O, antichlor, colourless, odourless, monoclinic crystals or white

granules, r.d. 1.69, m.p. 48oC, efflorescent in dry air, deliquescent in moist air, sodium hyposulfite, (deliquescent),

Stearic acid CH3(CH2)16COOH, powder, octadecanoic acid, m.p. 68oC to 69.5oC, (in fats).

Sulfuric acid

H2SO4, oleum, fuming sulfuric acid, oil of vitriol. concentrated H2SO4, clear, colourless, oily liquid, very hygroscopic, conc. 18 M, r.d. about 1.84, 18 mol per mL, r.d. fuming H2SO4: 1.92 gm cm-3, (for accumulators), battery acid r.d. 1.25 gm

cm-3, E513, dilute H2SO4, 3 M, store in cool place.

Pure sulfuric acid is called concentrated sulfuric acid. Sulfuric acid reacts violently with water to form hydrated hydrogen ions and hydrated sulfate ions. So the concept of dilution with water is inappropriate for the concentrated acid because a vigorous chemical reaction occurs that releases much heat. Do not add water to concentrated sulfuric acid. Dilute sulfuric acid by adding the acid slowly to water with continuous stirring. Wear eye protection when handling concentrated sulfuric acid. Water is less dense than sulfuric acid and will layer itself on top of the acid. At the acid / water interface, heat is generated by reaction of acid with water. This causes the water just above the interface to become very hot. When a suitable nucleating particle or surface is found, a large steam bubble forms, the middle section of the container boils suddenly and hot acid / water mixture is ejected from the container, often travelling several metres and causing serious chemical burns. If, the acid is slowly poured into water with stirring, the same amount of heat is liberated, but the boiling point of the solution is much higher than 100oC because of the presence of the sulfuric acid. The temperature of the solution may rise to 150oC, but boiling still does not occur. Sulfuric acid is highly corrosive to the skin and eyes. Wash sulfuric acid off the skin immediately with a large volume of water. A small amount of water simply brings about the acid water reaction and liberation of a great amount of heat, causing the remaining sulfuric acid to be even more corrosive. Hot sulfuric acid is a strong dehydrating agent and will cause organic materials, e.g. skin, to turn black because of the removal of water, leaving a residue of carbon. Sulfuric acid is not volatile, so neither the pure acid nor its solutions release vapour. However, strong

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heating of the acid may cause decomposition and boiling to form an aerosol of sulfuric acid droplets and sulfur dioxide gas that must not be inhaled. Sulfuric acid forms a spontaneously explosive mixture with potassium permanganate to form liquid manganese heptoxide. Similarly sulfuric acid forms a spontaneously explosive mixture with chlorate salts where gaseous chlorine dioxide forms. Dilute sulfuric acid solutions are far less dangerous than the concentrated acid because they do not dehydrate or reducing materials and do not form much heat when further diluted. Sulfuric acid collected from lead-acid batteries will be contaminated with lead.

Sulfurous acid H2SO3, 6% SO2 solution in water, clear, colourless solution, penetrating SO2 odour, oxidizes in air to sulfuric acid.

Tartaric acid

(CHOHCOOH)2, (CHOH)2(COOH)2, C4H6O6, racemic acid, 2, 3-dihydroxybutanedioic acid, colourless, odourless, transparent, monoclinic crystals, or white granules, r.d. 1.76, m.p. 168 to 170oC E334, from potassium hydrogen tartrate, sour taste food flavour, in winw and fruits, e.g. tamarind, tartrate salts, from potassium tartrate, tartar.

Tin (II) chloride

SnCl2.2H2O, stannous chloride, butter of tin, colourless, monoclinic crystals, absorbs O2 from air to form insoluble stannous oxychloride, r.d. 2.71, m.p. 37 to

38oC, (Also anhydrous SnCl2).

Titanium (IV) oxide

TiO2, titanium dioxide, colour white, opacifer, "white out" correction fluid, white pigments for tennis shoes, white paint, from mineral rutile, ilmenite FeTiO3, food additive, E171, the 3 mineral forms are anatase, brookite and rutile

1,1,1-trichloroethane

CH3CCl3, (E512), methyl chloroform, grease solvent, safer alternative to tetrachloromethane, (carbon tetrachloride, CCl4). Solvent in "white-out" correction fluids banned in many school systems. Ozone-depleting chemical being phased out of use. Mixed with active metals, e.g. Na, Mg, Al, , forms metal chloride and carbon in highly exothermic reaction. Substitute non-chlorinating solvents, e.g. acetone or ethanol.

Trichloromethane CHCl3, chloroform, colourless, mobile, clear, sweet taste liquid, distinct odour, Not

inflammable, vapour in flame may form poisonous gases, b.p. 61oC, store dark, cool place, former anaesthetic, solvent.

Trisodium phosphate (V)

Na3PO4.12H2O, sodium orthophosphate, "sodium phosphate", tribasic, trisodium orthophosphate, "TSP", colourless to white odourless, trigonal crystals, (sodium phosphate decahydrate Na3PO4.10H2O), (sodium phosphate dodecahydrate

Na3PO4.12H2O), r.d. 1.6, m.p. about 73oC, acidity regulator, food buffer, thickener E339.

Zinc oxideZnO, white to yellow, amorphous powder, r.d. 5.47, m.p. above 1 800oC, white pigment, zincite, white zinc, zinc white, Chinese white, spartalite, craft, zinc sun cream medicine and other skin problems.

Zinc sulfate ZnSO4.7H2O, colourless, odourless, white rhombic crystals or powder, r.d. 1.97,

m.p. about 50oC, efflorescent in dry air, anhydrous at 200oC, decomposes above 500oC, white vitriol, zinc vitriol, white copperas, gosla rite, in zinc deficiency

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Ammonia, ammonia solution, NH3 (aq) (COR 2672), (28%), 18 M

See: 12.11.3.10.2: Tests for ammonium radical, NH4+, free and combined ammonia, Nessler's reagent

Use in a fume cupboard. Use eye and skin protection. Do not mix ammonia with halogens, F, Cl, Br to avoid explosive reaction. Ammonia with solid iodine forms a highly unstable nitrogen triiodide complex, touch powder. Do not make touch powder. Solution of ammonia in water, NH3 (aq), colourless liquid, suffocating, pungent odour, absorbs CO2 from air < 10% actual NH3, "880" ammonia concentrated ammonia solution, 15.5 M, 880 ammonia

solution, 0.88 gm cm-3, aqua ammonia, ammonia water, ammonia hydrate, spirits of hartshorn, Liq. Amm. Fort 16 mol per mL, "cloudy ammonia" contains soap solution, E527, dilute ammonia solution, 6 M, needs cool storage, alkaline solution. Ammonia, NH3 (aq), or NH4OH, For 2 M solution., dilute 330 mL of 10% solution in 1 L water Ammonia solution, (10% ammonia solution), 5.3.4 Ammonia solution 3 M: dilute 200 mL, (28%), 14.8 M concentrated solution to 1 litre of water Ammonia solution 4 M: dilute 220 mL, (28%), 18 M concentrated solution to 1 litre of water, ("ammonium hydroxide"), Ammonia solution 4 M: Dilute 220 mL, (28%), 18 M concentrated solution to 1 litre of water, ("ammonium hydroxide"), Ammonia solution 3 M: Dilute 200 mL, (28%), 14.8 M concentrated solution to 1 litre of water, (Not "ammonium hydroxide, NH4OH". Ammonia solution is shown as NH3 (aq), because "(NH4

+)," ions and

"(OH-)," ions can be detected, but "NH4OH" cannot be detected.

medicines Zinc sulfide ZnS, white-yellow solid, soluble, sublimes, sphalerite or zinc blende, phosphor,

pigment. Zirconium (IV) oxide

ZnO2, zirconia, baddeleyite, for craft, fuel cell electrolyte.

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