School Science Lessons
Please send comments to: J.Elfick@uq.edu.au
Table of Contents
Table 2 Table of Elements
Table salt and rock salt: 19.1.16
Tagatose, C6H12O6, Aldoses
and ketoses (Table)
Talc, Mg3Si4O10(OH)2: 35.23.7 (Geology)
Talcum powder, talc, baby powder
Aldoses and ketoses (Table)
Tamoxyfen, C26H29NO, "Nolvadex", oestrogen receptor,
used for breast cancer treatment
Tannic acid, Tea
Tannins, plant polyphenols: 220.127.116.11
Tap water, Volume of gas dissolved in tap water: 18.104.22.168
Tap water, Weight of solids dissolved in tap water: 7.7.13
See: Tape Measures, (Commercial)
Tar, Coal tar products, creosote: 16.2.10
Tar, wood tar, hydrocarbon mixture from destructive distillation of
wood, e.g. birch, coal, organic substances
Tarnished silver, Clean tarnished silver: 15.3.16
Tartar emetic, K(SbO)C4H4O6. H2O
Tartaric acid, C4H6O6
22.214.171.124 Tests for tartaric acid
See: Tartaric acid, (Commercial)
TATP, Acetone peroxide: Contact explosives
Tautomer, Reactions of sulfamic acid: 12.18.7
TCP, Phenol, Carbolic acid: 16.1.0,
TDS, Total dissolved solids, water hardness, scale: 18.7.16
Tea, tannic acid
Tea tree oil
Teach manipulative skills, duties of a teacher: 3.2.4
Tear gas, C6H4(Cl)CHC(CN)2
Technical standard, chemicals 38.
TeflonTM, PFOA, perfluorooctanoic acid, CF3(CF2)6COOH:
35.20 Tenacity (Geology)
Tensides, alkylphenol ethoxylates: 9.2.30
Teeth and toothpaste: 9.226
Teflon , Polytetrafluoroetheylene, PTFE: 3.7.32
Temperature and rate of reaction: 17.2.3
Temperature, scales: 126.96.36.199.0
Temperature, Thermometers and temperature: 22.7.0
See: Thermometers (Commercial)
Tensides, alkylphenol ethoxylates: 9.2.30
Tephra, tuff: 35.21.7 (Geology)
tera-, T, × 1 million million, 1012
Terpenes (C5H8)n: 188.8.131.52
Terpenoids, isoprenoids (C5H8)n: 184.108.40.206a
Terpinenes (cyclic terpenes): 220.127.116.11b
Terpinyl acetate, C12H20O2
Test-tubes, glassware and microscope slides: 3.3.1
Test-tubes: 1.9 (List)
See: Test-tubes (Commercial)
Test tape, glucose tes-tape
3.4.5 Tests for electric polarity, potassium chloride with phenolphthalein
1.0.0 Tests for gases and vapours
22.7.9 Thermochromic substances
See: Test Strips Ammonia to Sulfide, (Commercial)
18.104.22.168 Testosterone, Steroids, sterols, steroid alcohols, natural steroids
Tetra-ethyl lead, lead
tetra-ethyl (in "leaded" gasoline)
Tetraamine copper (II)
Tetraamine copper (II) sulfate, [Cu(NH3)4(H2O)n]SO4,
Tetrabromophenol blue, C19H6Br8O5S,
disodium salt dye for X-ray examinations
Tetrachloroethylene, CCl2=CCl2, Stain removal:
22.214.171.124 (See Treatments: 2.),
Tetrachloromethane, CCl4, carbon tetrachloride
Tetrafluoroethylene, C2F4: 3.7.32
Tetramethylammonium hydroxide pentahydrate (CH3)4N(OH).5H2O,
Toxic, corrosive, avoid skin contact
Tetraterpenes C40 (eight isoprene units): 126.96.36.199.8
Tetraterpenoids, Carotenoids, C40: 188.8.131.52.8a
Tetrazolium chloride, C19H15ClN4 (2, 3, 5-
triphenyl- tetrazolium chloride), TTC, redox indicator, test for cellular
Tetrose sugars, Aldoses
THC (C21H30O2, tetrahydrocannabinol),
Hallucinogenic drugs, hallucinogens: 11.11. 9
Thermal capacity: 14.05
Thermal capacity, Specific heat capacity, calorimeters, heat measuring devices, C: 22.5.0
Thermal cracking, Cracking
Thermal decomposition: 3.22.0
Thermite reaction, thermit welding: 12.1.5
Thermochemistry, heat of reaction: 14.0
Thermochromic substances: 22.7.9
Thermoelectricity, thermocouple: 33.8.0
Thermometers and temperature: 22.7.0
Thermometers, Mercury in barometers and thermometers: 1.9
Thermoplastic polymers: 3.0.2
"Thermos" flask, Heat transfer by Dewar flask (vacuum flask): 22.2.8
Thermosetting polymers: 3.0.3
Thevetin A, C42H64O19, poisonois cardiac
Thevetin B, C42H66O18, poisonois cardiac
Thiamine, thiamin, Vitamin B1, C12H17ClN4OS, : 16.4.1.02
Thiazine compound: aromatic ring, one S atom, one N atom, four C atoms,
to prepare dyes, drugs, insecticides.
Thiazole derivatives, True alkaloids: 16.3.26
Thickeners, Stabilizers, food additives: 19.4.26
Thimerosal, C9H9HgNaO2S, preservative,
formerly used in childhood vaccines
Thinners, Flammable liquids, keep away from ignition
Thinners, solvents for oil-based paints, e.g. acetone, turpentine, white
spirit, MEK, DMK, toxic vapours
Thiocarbamide, NH2CSNH2, thiourea
Thiocyanates, anions (SCN)-
Thiols / mercaptans, CH3CH2SH): 184.108.40.206
Thiomersal, thimerosal, C9H9HgNaO2S
Thionyl chloride, SOCl2, sulfur
Thiophene (CH2)4S: 220.127.116.11.4
Aldoses and ketoses (Table)
Thymolphthalein, C28H30O4: 33 (indicator)
Thyodene (amylodextrin, C6H10O5)n,
indicator, blue with iodine, Toxic if ingested
Thyroxine, Table salt and rock salt: 19.1.16
Time, second: 18.104.22.168
See: Time, pendulum, timers, stopwatch, (Commercial)
Titan yellow, Tests for magnesium: 22.214.171.124 (See: 2.)
Titanite, sphene, CaTiSiO5, CaTi(OSIO4), calcium
Toluidine blue, Prepare toluidine blue solution: 3.25
Toluidines (m-toluidine, o-toluidine, p-toluidine), Highly toxic by all
See: Tongs (Commercial)
Tonic water, Quinine: 126.96.36.199
Tonic wines: 5.04.5
Tools for electrical experiments: 7.0.0
Top dressing and side dressing, Fertilizing: 9.12.3 (Agriculture)
Topaz, Al2(F2SiO4), Pegmatite: 35.21.3 (See: 2.) (Geology)
Torch battery, Dry cell torch battery: 33.4.2
torr, Pressure definitions: 12.1.01
Total dissolved solids (TDS) and suspended solids in water, Beer-Lambert
Total dissolved solids (TDS), water hardness, scale: 18.7.16
Touch powder, Nitrogen triiodide, NI3: 188.8.131.52
Touchstone, gold streak: 35.12.1
Toxicity: 4.0 (Safety)
Trace elements, Plant nutrients: 6.36
Trace elements soil test: 6.50.8
Trade mark, trademark, | TM | or | R in
a circle superscript |
Tranquillizers, Benzodiazepines: 184.108.40.206.5b
Trans fats, Omega-fatty acids: 220.127.116.11.2
Transammination, transposing an amino group within a compound
Transferring chemicals, Handling and transferring chemicals: 3.4.10
35.7 Transparency (Transparent, translucent, opaque, refraction) (Geology)
Transition elements: 1.12.0
See: Trays (Commercial)
Treated timber, Wood treated with copper chrome arsenate (CCA): 18.104.22.168
Tri(o-tolyl)phosphine, P(o-tolyl)3, monodentate ligand
Tri-sodium phosphate, Na3PO4.12H2O,
For 0.1 M solution, 38 g in 1 L water
Triammomium aurine tricarboxylate, Tests for aluminium: Aluminon
Triammomium phosphate (V)-3-water, ammonium phosphate
Triazacyclononane (tacn) (C2H4)3(NR)3,
Tribromomethane, bromoform (use < 50 mL), Harmful by all routes,
eye / lung Irritant
Tricarboxylic acids: 22.214.171.124
Trichloroacetic acid, CCl3COOH
Trichloramine, Chloramines in swimming pools: 18.7.23
Trichloroanisole, 2, 4, 6-Trichloroanisole, Cl3C6H2OCH3
Trichloroethanediol, Trichlorethanal, 1, 1, 1-trichloroethanediol, chloral
hydrate, toxic, drug addiction
Trichloroethanoic acid, trichloroacetic acid
Trichloroisocyanuric acid, TCCA, C3Cl3N3O3,
white crystalline powder, disinfectant, bleaching agent:
Trichloroisocyanuric acid, (GIF)
1, 1, 2-trichlorotrifluoroethane, Harmful if inhaled, ozone-depleting
chemical being phased out of use.
1, 1, 2-trichlorotrifluoroethane with active metals is highly exothermic,
e.g. Na, Mg, Al
(2, 4-D) (2, 4-dichlorophenoxyacetic acid): 16.7.6 (Agriculture)
(2, 4, 5-T) (2, 4, 5-trichlorophenoxyacetic acid): 16.7.7 (Agriculture)
Tricyclohexylphosphine (C6H11), monodentate ligand
Triethylenetetramine, TET, curing agent for epoxy resin adhesive, surface
Triethylenetetramine (trien), tetradentate ligand
Triglycerides, Glycerides, esterification of glycerol: 126.96.36.199.5
Trimethylphosphine (PMe3), monodentate ligand
Triphenylphosphine (PPh3), monodentate ligand
1.14 Tripod stands
See: Tripod Stands (Commercial)
Tris(2-diphenylphosphineethyl)amine (np3), tetradentate
Tris(2-aminoethyl)amine (tren) (NH2CH2CH2)3N,
Trifluoroacetic acid, CF3COOH, Corrosive by all routes, causes
severe burns, damages eyes
Trifluoroacetic acid, Solution < 1%, Not hazardous (used in chemical
1, 2, 3-trihydroxybenzene,
1, 3, 5-trihydroxybenxene,
3, 4, 5-trihydroxybenzoic acid, C6H2(OH)3COOH,
gallic acid: 188.8.131.52
Trilead tetroxide, Pb3O4, Lead (II/IV) oxide
Trillion, Different measurements, billion: 6.2.0
antibacterial, used with sulfamethoxazole
Triodomethane, iodoform, Prepare: 16.1.13
Triose sugars, 3C
Trioxoboric (III) acid powder, boracic acid, boric acid, orthoboric
Triple bond (has 6 electrons in the bond), e.g. Carbon monoxide, CO
Triple point and ice point of water:
Pb3O4, lead (II/IV) oxide
Toxic by all routes, cumulative poison
Tripod stands: 1.14
Tripotassium phosphate, potassium phosphate, potassium phosphate dibasic,
Harmful if ingested, skin irritant
Tris-(hydroxymethyl)-methylamine, Harmful if ingested
Trisodium-2-hydroxypropane-1, 2, 3-tricarboxyl
Trisodium citrate dihydrate,
Trisodium orthophosphate, Na3PO4
E339 (acidity regulator, emulsifier, mineral salt, laxative, textile
Trisodium phosphate, Na3PO4,
Tristearin, C57H110O6, stearin, tristearicacid
Triterpenes C30 (six isoprene units): 184.108.40.206.6
Triterpenoids, C30: 220.127.116.11.6a
Triton X-100, reduced, polyethyleneglycol, mono(p-octylphenyl ether
reduced, detergent, Harmful skin irritant
Tropain, C8H15N, 2, 3-dihydro-8-methylnortropidine
Tropane derivatives, True alkaloids: 16.3.27
Tropeolin O O (orange IV)
Tropylium, C7H7+, cationic ligand
Troy weight: 3.2.3
True alkaloids, Principle classes of alkaloids: 18.104.22.168
Tryptamine, Hallucinogenic drugs, hallucinogens: 11.11.9
(Table of amino acids)
Tryptophan, DNA codons
Tuff, tephra: 35.21.7 (Geology)
Turbidity, Tests for environment of river, lake or ocean: 18.5.1
Turbidity: 18.7.68 (Swimming pools)
See: Turbidity (Commercial)
Two-hole stopper, Stoppers, cork stoppers, rubber stoppers: 1.8
Tyndall effect, sunbeams: 22.214.171.124
Type metal, Alloys
Types of chemical reactions, Chemical reactions, : 12.2.0
Tyramine, Monoamine oxidase inhibitors (MAOI): 126.96.36.199
(Table of amino acids)
Tyrosine, DNA codon
Tyrosine, Separate amino acids with paper chromatography: 10.2.2.5
Talcum powder, talc
Talc, hydrated magnesium silicate, H2Mg3(SiO3)4,
[Mg3Si4O10(OH)2] (French chalk),
serpentine mineral (meerschaum pipes
and soap) (fine abrasive, absorbent, lubricant).
Talc that contains asbestos may be carcinogenic to humans.
Talcum powder can be used to repel ants that do not walk through it,
dust inside rubber gloves and shoes to slip on easily, dry
shampoo for human hair or dogs, stop squeak in floor boards, clean up
grease, absorb perspiration from skin and between sheets,
protect white clothing from grease, clean sand off wet skin.
Talcum powder is sometimes confused with "Baby Powder".
However, "Johnson's Baby Powder" contains Zea Mays (cornflour), starch,
tricalcium phosphate, fragrance (Aloe barbadensis leaf
juice), tocopherol (vitamin E).
It does not contain talc.
Cornflour is powdery starch synthesized from maize and used as a cooking
thickener (in USA "cornstarch") (in Australia "wheaten starch").
Tea, tannic acid
Tannic acid, tannin, C76H52O46 (Some chemists do not regard tannic acid as an acid.)
E181 Tannic acid
Prepare cup of tea: 12.13.15
Prepare ferric tannate with tea leaves: 16.8.2
Tannins, plant polyphenols: 188.8.131.52
Tea plant (Camellia sinensis), Theaceae
Tea with dilute sulfuric acid: 12.10.3
Tea with iron (II) sulfate: 12.10.1
Tea with iron (III) salts: 12.10.2
Tea with lime water: 12.10.4
Tannic acid and tea
E181 Tannic acid, tannins (from oak trees, tea) (clarifying agent)
Tannic acid is present in oak galls.
Make a solution of tannic acid by boiling cut pieces of oak galls in
Tannic acid is sold as a brown powder and was used in tannic acid jelly
for burns dressings.
Tea from Camellia sinensis, has a slightly bitter, astringent
Tea contains polyphenols, but tea does not contain tannic acid as previously
Tannic acid is a dyeing mordant, slightly toxic if ingested.
Use tea solution to polish linoleum, windows and mirrors, remove fish
smell and shine from seats of skirts or blue serge suits,
deodorizes feet, dye greying white fabrics, highlight brown hair, treat
sunburn pain, with lemon treat sore throat, diarrhoea, sore eyes,
burns, bleeding gums, broken finger nail, speed grass seed germination
and house plant growth, with lemon deodorize stuffy rooms,
clean and polish black lacquer and varnished woodwork, tenderize meat.
Tea tree oil
Tea tree (Melaleuca alternifolia),
Oil of Melaleuca, C10H18O, terpinen-4-ol, from
Melaleuca alternifolia, a paperbark tree (antibacterial, cosmetic,
Tea tree oil, Melaleuca alternifolia leaves, essential oil, antimirobial,
anti scabies, antifungal, in cosmetics, treat wound healing, period and breast pain.
Tantalum, Ta (Greek: Tantalos, mythical king who could not reach
fruit or water, tantalum acids are "out of reach" so no reaction),
in tantalite, columbite, other minerals usually with
Niobium, protective oxide so non-corrosive, very rare
Tantalum, coltan mineral.
Tartar emetic, K(SbO)C4H4O6. H2O
crystalline, poisonous, but used as expectorant and to treat schistosomiasis.
Tartaric acid, C4H6O6
Prepare fruit salts, health salts: 16.7.13
Thermal decomposition of acids: 8.2.4
Tartaric acid, racemic acid, α-hydroxy acid
L-(+)-Tartaric acid (2R, 3R)-(+)-Tartaric acid, L-Threaric acid, C4H6O6,
(CHOH)2(COOH)2, 2, 3-dihydroxybutanedioic acid,
colourless, odourless, transparent, monoclinic crystals, or white powder
granules, r.d. 1.76, m.p. 168 to 170oC E334, from potassium
hydrogen tartrate, sour taste food flavour, in wine and fruits, e.g.
tamarind, tartrate salts, from potassium tartrate, tartar.
Molecule is either dextrorotatory, d, or laevorotatory, l, so it refracts
light to the right or left, it has 2 mirror isomers (enantiomers).
Tartaric acid, manufactured from grape juice, is very weak acid ommonly
used as an ingredient in effervescing health salts.
Tartaric acid salt, potassium hydrogen tartrate (cream of tartar),
is used in baking powder.
Tartaric acid has similar chemical actions to citric acid in that it
liberates carbon dioxide gas from carbonates and bicarbonates, and it
forms hydrogen when warmed with iron filings or zinc.
It can clean copper coins by dissolving the surface copper (II) oxide.
Racemic means one-to-one mixture of left handed and right-handed, chiral,
forms of the same molecule.
Most chemical reactions produce products as racemic mixtures, whereas
biological reactions generally produce one or the other form
Racemic acid is a compound containing equal proportions of d- and l-
isomers of tartaric acid, so is optically inactive.
A tartrate is the ester or salt of tartaric acid.
azo dye, food additive E102, lemon-yellow colour, banned in some countries
Food colouring and ADHD: 19.9.1,
Synthetic food colours approved for use in Australia: 19.4.1 (See: Yellow shade).
See: Physiology Taste, (Commercial)
Taste of acids, solid acids in the home: 12.3.1
Cork taint of wine, "corky" wine (2, 4, 6-TCA): 3.29
Five senses (Primary): 1.15
Nose and smelling, taste, flavour, odour: 9.6.0
PTC tasters and non-tasters: 9.24.2
Sense of taste, the gustatory system: 9.246
Tasting chemicals: 3.4.9.
Technetium, Tc (Greek tekhnētos artificial), synthesized, dense,
heat-resistant, from uranium fission.
Radiopharmaceuticals, Technetium 99m: 7.2.4.
Tellurium, Te (Latin tellur earth), silver-white, brittle, metalloid,
similar to selenium, in gold and silver ores
Tellurium, in semiconductors (future supply shortfall)
Tellurium, pieces, powder, Highly toxic by all routes, display in sealed
Tellurium, natural tellurium, Te
Tellurides, tellurium compounds
Tellurium mineral, natural tellurium
Cadmium telluride thin films in solar cells to replace silicon panels.
Heat treatment of needles: 34.2.1
Heat treatment, razor blades, needles: 184.108.40.206
Heat treatment of steel needles, annealing, quenching, tempering: 3.64
Tempered glass, Prince Rupert's Drops: 220.127.116.11.
Teratogenic, causing malformation of a developing embryo or foetus
Terbene, dryer but some say
it extends time of drying (liniment, resists water and oil), Harmful,
flammable, irritant to skin and
Terbene, contact with combustibles may ignite (Ter. bene = tere bene
= rub well)
Pharmaceutical linament: Terbene 06 mL, Almond Oil 16 mL, Tincture of
ipecacuanha 8 mL.
tert-Butanol, tert-butyl alcohol,
tertiary butanol, tertiary butyl alcohol, trimethyl methanol
tert-Butanol, 2-methylpropan-2-ol, Highly flammable
tert-Butyl dimethylsilyl chloride
tert-Butyl dimethylsilyl trifluoromethanesulfonate
tert-Butyl ethyl ether
tert-Butyl hydroperoxide solution (70% in water)
Tests, chemical tests
Confirmation tests with original solution or solid: 18.104.22.168
Group tests instructions: 22.214.171.124
Food tests: 126.96.36.199
Tests for all substances: 2.0.0
Tests for an unknown substance, qualitative analysis: 188.8.131.52
Tests for gases and vapours: 1.0.0
Tests for swimming pools: 18.5.0.
Terbium, Tb (Ytterby, Sweden), stable in air but slowly oxidizes,
rare, future shortfall, green-yellow phosphorescence, with elements
Eu and Yb in TV screens
Terbium chips, foil, Tb
Terbium (III) acetate hydrate, C6H9O6Tb.xH2O
Terbium (III) acetylacetonate hydrate, C15H21O6Tb.xH2O
Terbium (III) bromide, Br3Tb
Terbium (III) chloride, Cl3Tb
Terbium (III) chloride hexahydrate, Cl3Tb.6H2O
Terbium (III) fluoride, F3Tb
Terbium (III) iodide, I3Tb
Terbium (III) nitrate hexahydrate, N3O9Tb.6H2O
Terbium (III) nitrate pentahydrate, N3O9Tb.5H2O
Terbium (III) oxide, O3Tb2
Terbium (III, IV) oxide, O7Tb4
Terbium (III) sulfate octahydrate, O12S3Tb2.8H2O
Terbium (III) trifluoromethanesulfonate, C3F9O9S3Tb.
Carbon tetrachloride, CCl4, tetrachloromethane, perchloromethane,
"dry cleaning fluid", "carbon tet", Not permitted in schools
The following chemicals are poisons and should never be used in a school
laboratory: carbon tetrachloride (CCl4, tetrachloromethane)
CFCs, chlorofluorocarbons, "Freons": 184.108.40.206
CFCs, atmosphere and greenhouse gases: 37.42.1
220.127.116.11 Methane with chlorine,
1-1-1-Trichloroethane, use instead of
Toxic by all routes, highly flammable, avoid inhalation, skin irritant
Tetrahydrofuran (don't use in school laboratory, but replace as solvent
with ethanol or acetone)
Tetrahydrofuran, Solution < 25%, Not hazardous, but do not ingest.
Thallium, Tl (Greek thallos green shoot, spectrum green line),
blue-white, soft malleable, similar to lead, toxic compounds
Thallium, in electronics, glass production.
Thallium (I) chloride, TlCl, thallium
chloride, thallous chloride, Extremely toxic if ingested or absorbed through
Not permitted in schools
Thallium (III) nitrate trihydrate
Thallium nitrate, Toxic if ingested or absorbed through skin, cumulative
poison, Not permitted in schools
Thallium (I) sulfate, Tl2SO4,
thallous sulfate, odourlesswhite rhomboid prisms or dense white powder,
rat poison, ant bait
Extremely toxic if ingested or absorbed through skin, slow acting cumulative
poison, Not permitted in schools.
Thermoluminescent substance emit light when heated, but do not themselves
decompose chemically, e.g. calcium oxide (limelight),
magnesium oxide, phosphorus (V) oxide (phosphorus pentoxide), fluorite,
Calcite glows when heated.
Thiocyanate ion: CNS- or [SCN]-
Thiocyanates: [RC(=O)SN] salts and esters of thiocyanic acid HSCN, e.g.
methyl thiocyanate (CH3SC N)
Cobalt (II) thiocyanate, Co(SCN)2, cobalt (II) thiocyanate,
Harmful, Environment danger, in Scott's reagent test for cocaine
Thiocyanates, Hazards: 3.7.18
Thiocyanate (thiocyanato), S-CN-, monodentate ligand
Thiocyanate, monodentate ligand.
Thionyl chloride, SOCl2, sulfur dichloride oxide, sulfur
oxychloride, Toxic by all routes, irritant vapour
Thionyl chloride, Prepare thionyl chloride: 18.104.22.168
Thionyl chloride with water forms hydrogen chloride gas and sulfuric
Thiosulfate ion: S2O32-
Thiosulfates with acids form sulfur dioxide gas.
Thiosulfates heated to decomposition form sulfur dioxide gas.
List of thiosulfates (not containing heavy metal ions, e.g. lead thiosulfate):
Thiosulfates, hazards: 3.7.19.
Thiourea, thiocarbamide (used as flame retardant and chelating agent),
Highly toxic, skin irritant, carcinogenic
Thiourea, Tests for bismuth: 22.214.171.124
Thiourea, Solution < 1%, Not hazardous, but do not ingest.
Thorium, Th (Old Norse Thor, thunder god), radioactive compounds,
high mp, in mining lamps and former gas light mantles, Toxic by
all routes, Not permitted in schools
SPADNS fluoride reagent solution, 500 mL,
indicator for thorium.
Aliphatic R-groups: 126.96.36.199
Available test reagents: 16.7.15
Conjugation in bacteria, Escherichia coli: 4.24
Lost nutrients in food: 19.3.03
Nutritional value (chicken feed): 22.20
(Table of amino acids)
Threonine, DNA codons, Threonine.
Thulium, Tm (Latin Thule, Ultima Thule, legendary most northern
habitation), lanthanide, rare.
Thymine, (5-methyluracil), (2,4-Dihydroxy-5-methylpyrimidine), Thymin, one of four constituent bases of DNA, pyrimidine nucleobase,
pyrimidone, human metabolite, (derived from hydrolysis of deoxyribonucleic acid or by methylation of uracil), in RNA thymine is replaced
with uracil, in DNA thymine binds to adenine to assist in stabilizing the nucleic acid structures.
DNA and RNA: 4.4.0
Nucleic acid, nitrogenous bases: 3.0.0
Nucleosides, nucleic acids, DNA, RNA: 188.8.131.52.
Nucleic acid nitrogenous bases: 3.0.0
See diagram: Heterocyclic compounds: pyrimidines, thymine
Thymol, phenolic terpene
Thymol, C10H14O, monoterpenes, C10,
(2 isoprene units)
Thymol, harmful if ingested but not in < 25 mg in throat lozenges:
Thymol 1-methyl-, 3-hydroxy-, 4-isopropylbenzene
Thymol blue (0.4% aqueous solution in 20% ethanol, UN number 1983),
Thymol blue: First (indicator, 1.2)
Thymol blue: Second ( indicator,
Thymol blue, indicator, 1st range: 34.0
Thymol blue, indicator: 2nd range: 34.1
Ajwain (Trachyspermum ammi),
Food used in plant respiration: 9.160
Lemon bergamot (Monarda
Meyer lemon (Citrus x myeri),
Meyer's albumen, adhesive, microscope slides: 2.3
Universal indicator: 36 (See: Experiment 1.)
2-isopropyl-5-methylphenol, "hydroxy cymene", monoterpene phenol, monoterpenoid,
from cymene, C10H13OH,
isomeric with carvacrol, large white colourless crystals or white crystalline powder, pleasant aromatic odour, from thyme oil, phenolic
compound, topical antifungal, antiseptic, antibacterial, pharmaceutical stabilizer, former vermifuge, thyme oil used in mouthwashes
and skin creams, cigarette additive, also used in perfumery, as a mould and mildew preventive, in microscopy, as a preservative,
antioxidant, flavouring; and laboratory reagent, in thyme and oregano.
See diagram: Thymol
Iodine is used in the muscles and in the thyroid gland as part of the
chemicals thyroxine and triiodothyronine.
Thyroxine is a hormone containing iodine, from thyroid gland, controls
Iodine deficiency causes hyperthyroidism and an enlarged thyroid gland.
The recommended daily allowance, RDA, is 150 pg.
Radioactive labelled iodine used to measure percentage uptake of it
by thyroid gland (RAI test).
Iodine poses fewer risks in school laboratories than the other halogens,
chlorine and bromine.
Do not inhale the acrid iodine vapour.
Avoid skin contact with solid iodine.
Iodine, whether as a solid, in solution or a vapour can temporarily
stain the skin.
Do not allow iodine to react with concentrated ammonia solution because
it forms nitrogen triiodide, NI3NH3 (touch powder),
is violently explosive.
Solid crystalline iodine is toxic by all routes of exposure and a highly
irritating vapour comes off from the crystals and iodine solutions.
Do not mix iodine with concentrated ammonia solution because the highly
explosive nitrogen triiodide may form.
The reactions of iodine with acetaldehyde or antimony metal are violently
Use of solid iodine by students should be limited to 0.2 g (the size
of about 2 rice grains), per experimental activity.
Atomic number: 53, Relative atomic mass: 126.905, r.d. 4.93, m.p. =
113.5oC, b.p. = 184oC.
Specific heat capacity: 218 J kg-1 K-1.
See: Tin Elements, Compounds, (Commercial)
Tin, Table of Elements
Tin, natural: 35.20.45 (Geology)
Tin-lead alloys: 5.5.10
Tin-plated beer can,
beverage can, aluminium can, "can", drink can, soda pop can, soft drink
Tests for hardness of lead, tin: 3.62.0
Tests for tin: 184.108.40.206 (See:
Tests for tin: 220.127.116.11
Prepare tin (IV) chloride: 12.20.2
Reactions of tin and tin compounds: 12.20.1.
Tin, Sn (Old English
tin), silver, lustrous, malleable metal, in cassiterite, granulated,
pellets, foil, sheets, powder (tin-plated jam tin),
pewter, metal foil (0.13 mm), metal granulated, metal powder.
Tin is used in electrochemical cells, reactivity of metals, metal displacement
Tin with silver and mercury in dental "amalgam" is used for teeth fillings.
Also, bronze is an alloy of copper containing small amounts of
tin or arsenic. Tin fine dust and tin fumes are a heavy metal hazard.
Tin-plated jam tin, pewter is a ductile, malleable metal, resists corrosion,
is available as granules, pellets, foil and powder, is extracted
from the ore cassiterite, [tin (IV) oxide, SnO2], and used
in alloys and the shiny protective plating of "tin cans" (tin plate) and
aluminium drink-cans, and in alloys and solders.
It reacts with dilute HCl or H2SO4 to form H2
and metal ion, reacts with concentrated oxidizing acids,
HNO3 or H2SO4 to produce high oxidation
number ions, and sulfur dioxide SO2 or nitrogen dioxide, NO2.
No reaction with water.
Heated powder forms oxide.
The "silver paper" used in wrapping is usually tin foil.
Atomic number: 50, Relative atomic mass: 118.71, r.d. 7.28 (white),
5.75 (grey), m.p. = 232oC, b.p. = 2270oC.
Specific heat capacity: 218 J kg-1K-1.
Cassiterite, tinstone, SnO2: 35.20.7
Group 2 tests for Bi3+, Cd2+, Cu2+,
Reactions of tin and tin compounds: 12.20.1
Separate by melting points, tin from tin and carbon mixture: 3.18
Weight of tin in solder: 17.6.6.
Copper-tin alloys, bronze: 5.5.7
Tin (II) bromide
Tin (II) chloride, stannous chloride, SnCl2
Tin hydroxide, amphoteric
Tin (II) oxide, SnO, amphoteric
Tin (IV) bromide
Tin (IV) chloride, stannic chloride, tin
Tin (IV) fluoride
Tin (IV) oxide, SnO2, tin dioxide, tinstone, tin oxide, tin
ashes, stannic oxide for craft, from cassiterite
Stannic (IV) chloride pentahydrate
Tin-lead alloys: 5.5.10.
Tin (II) chloride,
stannous chloride, SnCl2
Tin (II) chloride, SnCl2.2H2O, Harmful if ingested
Tin (II) chloride absorbs oxygen from the air to form water insoluble
tin oxychloride, keep in airtight container
Tin (II) chloride forms explosive mixtures with oxidizing agents, e.g.
nitrates, peroxides, nitrites, permanganates
Tin (II) chloride, hydrated, tin (II) chloride-2-water, SnCl2.2H2O,
tin salt, crystals,
Tin (II) chloride, For 0.5 M solution, 113 g in 170 mL concentrated
HCl, dilute to 1 L + add tin foil
Electrolysis of tin (II) chloride solution: 15.5.20
Prepare solutions, tin (II) chloride: 5.4.18.
Tin (II) chloride, anhydrous, powder, SnCl2,
tin (II) chloride dihydrate, SnCl2.2H2O, stannous
chloride dihydrate, 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
Tin (IV) chloride,
Tin (IV) chloride (use 0.1 M solution to test for cations), Harmful
if ingested, corrosive
Tin (IV) chloride, Solution < 5%, Not hazardous
Tin (IV) chloride forms an explosive mixture with turpentine
Tin (IV) chloride with water forms hydrogen chloride gas.
Tin (IV) chloride-5-hydrate, SnCl2.5H2O, For 0.1
M solution, 35 g in 1 L water
Prepare tin (IV) chloride, SnCl4: 12.20.2
Tincture of iodine
Prepare herbal tinctures, 17.0.0
Herbal tinctures: 5.04.4
Prepare iodine crystals with tincture of iodine: 18.104.22.168
Prepare iodine solution, tincture of iodine: 22.214.171.124.
Tincture of iodine
126.96.36.199.8 Povidone, Polyvinyl
The word "tincture" means add a small mount of a substance to the main
substance or a tinge of something added to the main substance
to change the colour.
A tincture is an alcoholic solution of non-volatile substances with
the alcohol acting as a solvent and preservative.
Tincture of iodine, used in medicine, is iodine dissolved in ethanol.
Tincture of iodine because if sodium iodide not added, iodine would
otherwise be insoluble, 2-7% KI or NaI solution in ethanol and
water, about 2 g iodine and 2 g sodium iodide in 100 mL in 40-60% ethanol,
contains soluble triiodide anion I3-, disinfectant, antiseptic
and starch test
Nowadays, the tincture of iodine that used to be found in most home
medicine chests is often replaced by Povidone
iodine, e.g. Betadine.
Lugol's iodine solution is elemental iodine and potassium iodide.
See: Titanium Elements, Compounds, (Commercial)
Titanium, Ti, Table of Elements
Titanium properties: 188.8.131.52a .
Titanium, Ti (Greek titan god), transition
metal, in clays and minerals
Titanium dioxide, TiO2
See: Titanium Dioxide (Serrata)
brookite mineral, in self-cleaning concrete
Titanium tetrachloride, Toxic by all routes.
Titanium tetrachloride with water forms hydrogen chloride gas and titanium
Titanium tetrachloride bottles may be under pressure because of formation
of hydrogen chloride
Tantanite, calcium titanium silicate, source of titanium and jewel stone,
absorbs ultra-violet light so used to prevent sunburn
Tantanite, titanium silicate, source of titanium, jewel stone
Titanium sun glass rims
Titanium Ion Bands, Oregon Scientific "negative ion bracelet", pseudo
Titanium ore was discovered in 1791, but pure titanium not produced
until 1910 .
Titanium is strong, lustrous, silver colour, low density.
It is resistant to sea water corrosion, aqua regia and chlorine.
It can be welded with lasers but not soldered.
Titanium used in aeroplane framework and turbine blades of turbojet
engines, bicycles, cars, jewellery and craft ware, walls of
Guggenheim Museum in Bilbao.
Titanium inserts, e.g. screws are tolerated by the human body and will
undergo osseo-integration and form a strong surface coating of
titanium oxide to form strong bonds will bones.
um turnings are very hard sensitive to friction, and used for
silver sparks in fireworks
Titanium is a chemical element with the symbol Ti and atomic number
It is a lustrous transition metal with a silver colour, low density
and high strength.
It is highly resistant to corrosion in sea water, aqua regia and chlorine.
Atomic number: 22, Relative atomic mass: 47.867, r.d. 4.5
Specific heat capacity 54 J kg-1 K-1.
Titanium (II) chloride, TiCl2, titanium dichloride
Titanium (III) chloride, TiCl3, titanium trichloride
Titanium tetrachloride, Toxic by all routes
Titanium (III) fluoride
Titanium (III) sulfate solution
Titanium (IV) butoxide.
Titanium (IV) chloride, TiCl4, titanium tetrachloride (tickle),
volatile metal halide, liquid at room temperature, forms clouds in humid air
Titanium (III) chloride, TiCl3, titanium trichloride, common
titanium halide, paramagnetic derivatives
Titanium (II) chloride, TiCl2, titanium dichloride, highly reactive black solid.
Titanium (IV) isopropoxide
Titanium (IV) oxide, anatase, TiO2,
Titanium (IV) propoxide, Ti(OC3H7)4
Brookite, mineral, TiO2
Ilmenite, mineral, FeTiO3
35.20.37 Rutile, TiO2,
titanium (IV) oxide
Sagenite, TiO2, mineral
Titanium (IV) oxide
Titanium (IV) oxide, powder, TiO2, titanium dioxide, colour
white, opacifer, "white out" correction fluid, white pigments for tennis shoes,
household white paint, from mineral rutile, ilmenite FeTiO3, food
additive, E171, the three mineral forms are anatase, brookite and rutile.
See: 6CH Titrations, (Commercial)
Titration Neutralization of soluble acid and base, prepare salts: M1
Titration, neutralization: 184.108.40.206
Titration, heat of a neutralization reaction: 3.82
Titration of acids with bases: 3.78.
3.78 Titration of acids with
Put 20 drops of a dilute acid, e.g. vinegar in a test-tube.
Add one drop of indicator, e.g. methyl orange or phenolphthalein.
Add a dilute base drop by drop, and count the drops.
Within experimental error, it will always take the same number of drops
to neutralize the 20 drops of acid.
If using the same dropper, a teat pipette is used.
If the concentration of the acid is known, the concentration of the
base can be estimated by comparing the numbers of drops of acid
and drops of base that just react.
Anabasine, C10H14N2 (test for smoking)
6H4O2, para-quinine, cyclohexadiene-1, 4-dione, in coal and tobacco smoke
9.213.4 Virus list, tobacco mosaic virus
Pipe clay is fine white clay formerly used for tobacco pipes, pottery and leather whitening.
16.7.28 Tests for cigarette smoke
16.7.29 Toxic effect of drugs on water fleas (See: 2.2).
Ethylbenzene, C8H10, in tobacco
OTO test for swimming pools: 220.127.116.11
For testing water in school swimming pools do not use OTO test, but
use DPD test:
DPD test for swimming pools: 18.104.22.168
Sensitivity to drugs determined by genes: 9.4.1.
Highly toxic if ingested, carcinogenic impurities, Not permitted in
Tolidine, 2-tolidine, o-Tolidine, Orthotolidine, Diaminoditolyl, Diaminotolyl,
Bianisidine, Tolidine blue, 3, 3'-Dimethylbenzidine,
Purchase: o-Tolidine, 97%, powder, 3, 3 -Dimethylbenzidine, 4, 4 -Bianisidine
Tolidine derived from toluene.
It is used as a reagent to test for gold and for chlorine in water.
Tollens' reagent, ammoniacal silver nitrate solution, Toxic if ingested,
corrosive to skin
Be careful! Tollens' reagent evaporated to dryness is explosive
Tests for aldehydes, Tollens' test: 22.214.171.124.
Toluene, methylbenzene, CH3C6H5, from
benzene C6H6, by replacing a H by a CH3
Toluol, toluene, coal tar product
Low cost: from hardware stores, paint stores
For general solvent and chromatography, but use ethanol, not toluene,
as solvent for dilute solutions
Toluene is a curing agent for epoxy resin adhesives, surface coating,
irritant, in nail lacquer
Toluene, methylbenzene, toluol, Toxic by all routes, highly flammable,
do not inhale vapour
Toluene, Solution < 12.5%. Not hazardous
Toluene diisocyanate, toluene mixd isomers, Highly toxic by all routes,
Toluene diisocyanate, Solution / mixture < 0.5% not hazardous
Toluene, flammable liquids, Flammable organic chemicals: 15.7.0 (See: Table 15.7.0, Toluene)
Toluene, octane number: See diagram 16.1.1h
Antioxidants (BHT), E321: See diagram 126.96.36.199
Aromatics, benzene, toluene, naphthalene: 188.8.131.52
Coal tar products, creosote: 16.2.10
Relative sweetness of some artificial sweeteners: 19.2.8
Separate by chromatography, green leaves: 3.24
Steam distillation, water and fat content, food: 10.5.5.
Town gas was the main domestic gas, a mixture of coal gas and carburetted
water gas, energy density about 20 MJm-3, was
previously used on school laboratories, but nowadays the gas is usually
natural gas, i.e. mostly methane CH4, or LPG, bottled gas,
mostly propane, C3H8.10.55
Household gas, laboratory
gas, "lab gas"10.55.
Triboluminescent minerals emit light when squeezed, e.g. Sphalerite,
Trichlorethylene, trichlorethene (C2HCl3), Toxic
if ingested or inhaled, carcinogenic, ozone-depleting chemical being phased
Trichlorethylene, Solution < 1%, Not hazardous but do not ingest.
Dilute with ethanol.
Trichlorethylene with active metals is highly exothermic, e.g. Na, Mg, Al.
acid, trichlorethanoic acid, CCl3COOH, C2HCl3O2
Highly toxic by all routes, highly corrosive to skin and eyes, highly
Trichloroacetic acid, Solution < 1%, Not hazardous.
1, 1, 1-trichloroethane,
CH3CCl3, methyl chloroform, Toxic if ingested, do
not inhale vapour
Trichloroethane (1, 1, 1-trichloroethane), Solution < 25%, Not hazardous
ACS reagent (may contain 0.05% low alkyl epoxide as stabilizer), "Chlorothene",
(E512), methyl chloroform, grease solvent, safer
alternative to tetrachloromethane (carbon tetrachloride, CCl4).
Solvent in "white-out" correction fluids, but banned in many school
systems because of "sniffing".
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 for non-chlorinating solvents, e.g. acetone or ethanol.
Do NOT store or use in school science laboratories.
Methane with chlorine: 184.108.40.206,
Prepare trichloromethane: 16.1.14
Reaction of ethyl alcohol with bleaching powder: 220.127.116.11 (Dangerous experiment)
Trichloromethane, cleaning agent, solvent: 2.20.4
Trichloromethane, methane trichloride, TCM, Freon 20, Refrigerant R20,
Toxic by all routes, Not permitted in schools, harmful, local
purchase, anaesthetic, 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 irritant, possibly carcinogenic.
C6H15NO3, "tea", viscous liquid, Harmful
if ingested, skin irritant, avoid vapours
N(CH2CH3)3, Harmful, highly irritant vapour,
alkaline skin irritant
Triethylamine, Solution < 20%, Not hazardous.
2, 4, 6-trinitrophenol (NO2)3C6H2OH,
picric acid, trinitrophenol, carbazotic acid, Toxic, irritant, Not permitted
2, 4, 6-trinitrophenol, yellow crystals stain skin yellow, Explosive when
dry and compacted
2, 4, 6-trinitrophenol, If crust forms at neck of bottle, do not open
bottle because crust may explode.
sodium orthophosphate, "sodium phosphate", E339,
Trisodium phosphate, Na3PO4.12H2O,
For 0.1 M solution, 38 g in 1 L water
"TSP", trisodium phosphate, cleaner (brand name, may not include phosphates!)
Sodium phosphate, Na3PO4, sodium orthophosphate,
trisodium phosphate, sodium phosphate tribasic dodecahydrate, Na3PO4.12H2O,
TSP, trisodium phosphate dodecahydrate, "sodium phosphate", tribasic,
colourless to white odourless, trigonal crystals, r.d. 1.6,
m.p. about 73oC, acidity regulator, food buffer, thickener E339.
Trypsin, protease in human digestion system, formed from trypsinogen
in the pancreas, converted to its active form by enteropepidase
in the small intestine, hydrolyses carboxyl group of arginine or lysine.
Tryptose, peptone from meat and soybean meal, mixture of water-soluble
peptides, no chemical formula.
Tung oil from nut of tung oil tree, Aleurites fordii, Euphorbiaceae
Tung oil is used to penetrate wood, seal against moisture in paints
and varnishes, because it dries hard.
Tungsten, W, Table of Elements
Tungsten properties: 18.104.22.168
Incandescent, filament lamp, light bulb: 33.4.0
Scheelite, CaWO4, calcium tungstate: 35.20.38
Tungsten, W, Chemical reactions: 22.214.171.124
Tungsten carbide, Carbides (C4-): 126.96.36.199
Wolframite: 35.20.48 (Mineral).
Tungsten, W (formerly wolfram) (Swedish tung
heavy sten stone), white-grey metal, dense, transition element,
tungsten carbine used for very hard metal alloys, steels, jewellery,
fluorescent lighting, weights and counterbalances, light bulb filaments,
vacuum tube filaments, heating elements, electrodes.
Tungsten, highest mp, so in electric filaments and steel alloys.
Tungsten sulfite in high temperature lubricants.
Available as tungsten wire.
Tungsten is from wolframite (MnFe)WO4, scheelite CaWO4.
Tungsten is not affected by dilute acids, used in steels and lamp
filaments, tungsten carbide, WC, black powder, used in cutting tools
because has Mohs scale 9.5.
The tungsten filament in a light bulb reaches about 2, 300oC.
It has the highest melting point of all metals.
Tungsten alloy, high density 15.4-18.5 g / cc (80-97W), with components
of W-Ni-Cu, W-Ni-Fe or W-Ni-Cu-Fe for different
applications of radiation shielding, crankshaft counterbalance for automobiles,
defence applications of kinetic energy penetration, counterbalance for
racing car, yacht, aircraft, sports fittings parts, e.g. golf, fishing
weights and sinkers, counterbalance in oil exploration, medical shields.
Atomic number: 74, Relative atomic mass: 183.85, r.d. 19.3, m.p. = 3, 422oC,
b.p. = 5, 660oC.
Specific heat capacity: 130 J kg-1 K-1.
Dienes, isoprene units: 188.8.131.52.2
Prepare turpentine copying fluid: 9.1.4.
Terpenes have linked isoprene units as in natural rubber.
Use turpentine + steel wool to remove scuff marks on the floor.
Use turpentine solution for washing blankets before storage, to deter
Use turpentine to remove paint stains.
Mineral turpentine, "mineral turps", paint thinner, Toxic by all routes,
Turpentine, Mixture / solution < 25%, Not hazardous
Mineral turpentine, "turps", cheapest paint and ink solvent, mixture
of petroleum hydrocarbons, avoid vapours, eye and skin contact.
mineral turps, oil-based paint cleaning solvent, petroleum fraction
b.p. 150oC - 200oC
Mineral turpentine contains aliphatic hydrocarbons, Toxic by all routes
Mineral turpentine, "Turpentine Odourless Thinner", "Turpenoid", solvents
with no smelling hydrocarbons so may be undetected
Mineral turpentine, "turps", is the cheapest solvent for oil-based paint
and ink solvent, mixture of petroleum hydrocarbons, avoid
vapours, eye and skin contact, toxic by all routes of exposure, highly
("Turpentine Odourless Thinner", "Turpenoid", are solvents with strong
smelling hydrocarbons removed so may be undetected).
"Turpenoid natural", non-toxic, non-flammable, alternative to mineral
True turpentine, vegetable turpentine, spirit of turpentine, wood turpentine,
gum spirits, gum turpentine, from pine trees (FP 35oC),
Gum turpentine, gum spirits oil of turpentine, originally, "true terpentine",
called Chian terpentine from Pistacia
terebinth tree, Anacardiaceae
Nowadays, gum turpentine from various pine trees, contains contains
terpenes, mainly, α- and β- pinene,
Gum turpentine has pleasant odour but possible skin irritant vapour,
less toxic than mineral, turpentine, highly flammable and reacts
violently with chlorine gas and explosively with chlorine compounds,
e.g. tin (IV) chloride.
Rosin is a solid amber residue made by the distillation of turpentine
from pine stumps, used for adhesives, varnishes, violin bows.
12.20.1 Reactions of tin and
1. Pass hydrogen sulfide through tin (II) chloride solution.
Note the precipitate that is insoluble in dilute hydrochloric acid.
Sn2+ + S2- --> SnS (s)
Filter off the precipitate and wash with distilled water.
Transfer it to an evaporating basin and add yellow ammonium sulfide
The precipitate dissolves.
Oxidation by the free sulfur in the ammonium sulfide occurs, so the
S in the equation come from the ammonium sulfide.
(NH4)2S + SnS + S --> (NH4)2SnS3
Add dilute acid to the ammonium thiostannate to precipitate tin (IV)
2. Add drops of sodium hydroxide solution to tin
(II) chloride solution.
Note the white precipitate of tin (II) hydroxide that dissolves in excess
sodium hydroxide to form sodium stannite.
Sn2+ + 2OH- --> Sn(OH)2 (s)
Sn(OH)2 + 2OH- --> SnO22-
+ 2H2O (stannite ion = SnO22-).
3. Add drops of ammonium hydroxide solution to tin
(II) chloride solution.
Note the white precipitate of tin (II) hydroxide that is not soluble
in excess of ammonium hydroxide.
4. To show that tin (II) chloride is a powerful
reducing agent, add tin (II) chloride solution to solutions of the following
Reduction occurs with every reagent.
Iron (III) chloride forms pale green iron (II) ions.
Potassium permanganate forms manganese (II) ions.
Potassium dichromate forms green chromic ions.
12.20.2 Prepare tin (IV) chloride
1. Use a fume cupboard
Put sand into the retort protect the glass during heating, followed
by 5 cc of granulated tin.
Insert the delivery tube and connect to a chlorine apparatus.
Heat the retort while chlorine passes over.
Note the ignition of the tin, the fine white crystals in the upper part
of the retort, and the yellow distillate of tin (IV) chloride.
The white crystals are SnCl4.5H2O, due to traces
of moisture in the apparatus.
Sn + 2Cl2 --> SnCl4.
2. Add drops of water to the tin (IV) chloride mixture
and heat the mixture.
Test for hydrogen chloride.
The white precipitate is hydrated tin (IV) oxide or a tin (IV) acid.
SnCl4 + 4H2O --> SnO2.2H2O
3. Add ammonium hydroxide solution to the tin (IV)
chloride mixture and heat the mixture.
Divide the suspension of hydrated tin (IV) oxide into two parts.
To show the amphoteric nature of hydrated tin (IV) oxide, dissolve part
A in sodium hydroxide solution and dissolve part B in
SnO2.2H2O + 4HCl -->- SnCl4 + 4H2O
SnO22H2O + 2NaOH -->- Na2SnO3
(Note: Na2SnO3 = sodium stannate).