Know about dioxins and Agent orange, used in warfare.

School Science Lessons
(appendix E)
2025-03-02

Low-cost chemicals, common substances
Contents
16.0.0 Low-cost chemicals, common substances

16.0.0 Low-cost chemicals, common substances:
Consumables
Albumen
Alka-Seltzer (Experiments)
Antacids (Experiments)
Asphalt (Experiments)
Baby powder
Baking soda (Experiments)
Base metals
Beeswax
Beverage can (Experiments)
Brass (Experiments)
Bronze (Experiments)
Buffers (Experiments)
Cellophane (Experiment)
Canola oil
Cobalt chloride
Collagen
Collodion
Cu acetoarsenite
Corn oil
Cornstarch
Crayons
Creosote
Collodion
Cresol (Preparations)
Cresylic acid
Cyanuric acid
DMSO
Desiccants
Dioxin, Agent orange, PCBs
Erucic acidacid
Eucalyptus oil
Gases, "lab gas"
Gelatin
Glass wool
Glazes
Glycogen
Hair
Inks
Invertase
Isocyanuric acid
Javelle water
Lavender oil
Lemon juice
Linseed oil
Liver of sulfur
LPG
Mg ribbon
Matches
Metals
Metaldehyde
Inks
Metglas
Naphthalene (Experiments)
Neatsfoot oil
Noble metals
Paraffin oil, "kerosine"
PFAS chemicals
Putty
Re-lighting candles. Magic candles
Resin
Salad oil
Shellac
Soap
Starch (Experiments)
Steel wool
Tartar emetic
Talcum powder
Tea
Tincture of iodine
Tung oil
Turpentine
Uric acid
Vanilla
Vaseline
Water
White spirit
Wine

16.14.0 PFAS chemicals
16.14.4 PFAS chemicals perfluoroalkyls and polyfluoroalkyls
16.14.3 PFOS, perfluorooctanesulfonic acid
16.14.1 PBDE, pentabromodiphenyl ether, C12H5Br5O
16.14.2 PFOA, perfluorooctanoic acid, C8HF15O2

16.15.0 Dioxin, "Agent orange", PCBs
Dioxin, C4H4O2, 1,2-Dioxin, o-Dioxin, 1,2-Dioxacyclohexadiene, was first used to kill noxious weeds, e.g. privet and blackberry.
At first it caused birth defects in animals and chloracne rash in workers due to a dioxin impurity C12H4Cl4O2, (2,3,7,8-Tetrachlorodibenzo-p-dioxin), (TCDD).
This impurity occurs as white crystals or tan crystalline powder and can cause cancer according to The Environmental Protection Agency (EPA).
Agent Orange was used first by the UK military in Malaysia and later by the US military to defoliate jungle regions in Vietnam.
PCBs, polychlorinated biphenyls, are mixtures of up to 209 individual chlorinated compounds, called congeners.
PCBs have no known smell or taste and the manufacture was stopped in the U.S. in 1977, because they build up in the environment and can cause harmful health effects.

Albumen, albumin
Albumen, albumin, Experiments
1. Albumen is egg white, white of an egg, albumen flakes, albumen egg powder.
2. Albumin is any protein soluble in water and can be coagulated by heat.
3. Albumin soluble protein in blood serum, serum albumin in blood serum.
Alphlactalbumin in milk, a globular protein.
Albumin from bovine serum is sold as Bovine Serum Albumin, and Bovine Plasma Albumin, (BSA).
Albumin from humans is sold as Albumin, Human, tested negative for HIV and HBSAG [surface antigen of hepatitis B virus (HBV)].

Alka-Seltzer
Alka-Seltzer (trade name) is a drink to relieve headache and stomach discomfort.
Contents: Aspirin, Sodium hydrogen carbonate, Citric acid.
sodium hydrogen carbonate + citric acid --> carbon dioxide
Dilute acids with sodium hydrogen carbonate: 12.3.10
Effervescent tablets, health salts, sodium bicarbonate (baking soda): 11.1.1 (See 2.)
Sodium hydrogen carbonate, (NaHCO3)
Green hair and faded hair from swimming pools: 18.7.15.1
Seltzer water: 3.34.3.2.
Use Alka-Seltzer to clean toilets, vases, jewellery, thermos pans with burned-on grease, and unclog a drain.
Use Alka-Seltzer + vinegar to soothe insect bites.

Antacids
Gastro-oesophageal reflux (reflux) is caused by action on the oesophagus of acid from the stomach, treated by neutralizing the acid with bicarbonate of soda or by chewing an indigestion tablet containing carbonate salts.
For example:
1. Alka-Seltzer (trade name)
2. Mylanta (trade name), "Double Strength, contents": Magnesium hydroxide, ammonium hydroxide - dried, Simethicone
3. Rennie (trade name) Spearmint, contents: Calcium carbonate, magnesium carbonate, magnesium hydroxide + other ingredients

Asphalt
Asphalt, bitumen, Experiments
Asphalt, (bitumen tar pitch), is black plastic solid from the final residues left after volatile substances are removed by fractional distillation of the petroleum of natural occurrence.
It is used for road construction and sealing roofs.
Asphalt is a natural organic material, often occurring in tar pits, with a hydrocarbon base that softens with heat and has been used for thousands of years for basins, impermeable water ways, sealing roof shingles, and caulking wooden ships.
English sailors on naval sailing ships were called "tars", from their use of tar for waterproofing.
Bitumen is any naturally occurring asphalt or any black, viscous hydrocarbon mixture.
Bituminous coal burns with a bright smoky flame.

Baking soda

Baking soda, Experiments
Baking soda is sodium hydrogen carbonate, sodium bicarbonate, (NaHCO3), bicarbonate of soda, "bicarb".
Use baking soda to:
1. Clean baby utensils, barbecue grills, bathtubs, bathroom tiles, coffee pots, vacuum flasks, refrigerators, stainless steel sinks, microwave ovens, dishcloths, and laundry towels.
2. Remove fruit juice stains, crayon marks, perspiration from cloth, and cookware burnt-on food.
3. Soften and whiten woollen socks, remove tarnish from silver and coffee stains.
4. As a hair conditioner, to increase strength of liquid laundry detergent and bleach, and maintain septic tanks.
5. Deodorize cutting boards, carpets diapers, food containers, garbage disposals, dishwashers, clothes, shoes.
6. Treat rashes, insect bites, sunburn, sore feet and use as toothpaste, mouth wash, under arm deodorant, and remove vomit odour.

Beverage can
Beverage can, Beer can, (Experiments)
Beverage, prepared drink, but not water, e.g. tea, soft drink, alcoholic drink.
Beverage can, aluminium can, beer can, "can", drink can, drinking can, soda pop can, soft drink can, tin-plated steel can
1. Beverage cans are usually cylindrical containers made of aluminium or tin-plated steel in which food and drink can be stored and hermetically sealed.
2. The sizes and composition of the walls of the can may vary as follows:
2.1 USA and Canada, "aluminium cans", 355 mL, 92-97% Al, <5.5% Mg , <1.5%, Mn, <0.15 % Co.
The empty beverage can weight is 15 g.
2.2 Australia, 375 mL
2.3 Europe, China, India, 330 mL
3. Aluminium is highly suitable as a packaging material for beverages, but have a protective epoxy resin polymer coating applied on the inside to prolong storage life so acids and salts in certain foods or beverages do not contact the metal.
4. Aluminium does not corrode easily.
5. Aluminium has density 2.70 g / cm 3 , compared with steel 7.86 g / cm 3 , so it is very light and cuts down on transport costs.
6. Aluminium transfers heat 2.4 times faster than iron, and very thin sheets can be produced, so heat is lost and gained by aluminium very quickly, giving it ideal qualities for cooking and as a cold drink container.
7. Aluminium can be rolled into extremely thin foil, and can be cast and joined, yet still retain much of its strength, so less of it is needed as a light packaging material.
8. Aluminium has melting point of 660 o C, compared with 154 o C for iron, so less energy is required for processing and recycling it.
9. The lids of beverage cans may be a different composition than the cup portion of the can.
10. The history of opening beverage cans
* Knife or bayonets were first used to open hermetically-sealed cans at home and during military service.
* Can piercers church keys used a lever action to dig a triangular hole in the top of the beverage can with the cut metal being pushed inside the can.
*. "Pull tabs", ring pulls, pulled of a section of the top of the beverage can, so that the ring and cut metal piece became detached.
However the separated pull tabs became an environmental hazard, and the opening in the top of the beverage can had sharp edges, so adolescents could use them as dangerous rings on small fingers.
Some old people did not have the strength or dexterity to use pull tabs.
"Push tabs" detached an opening in the top of the can by pressing down, but people could cut their fingers on the cut metal.
* "Stay-tabs", stay-on tabs, pop-tabs, are favoured nowadays, because they are easy to use, and cannot be detached to cause pollution or injury.
11. Tapping a shaken soda pop can
To avoid an explosive emission of beverage and gas from a shaken soda pop can, some people lightly tap the side of the upright can before pulling on the pull tab.
This practice may be regarded as an urban myth.
Tapping may release some bubbles from adhering to the walls of the soda pop can to collect at the top of the beverage just inside the ring pull.
So when the drink-can is opened, these bubbles do not push through the beverage, but push out some beverage explosively.
The time taken for the tapping gives some time for the carbon dioxide to dissolve back into the beverage, compared with a soda pop can being opened immediately after the shaking.
The beverage is emitted less forcefully if the soda pop can is opened very slowly, or put back in the refrigerator to increase the absorption of carbon dioxide.

Birdlime
Birdlime, bird lime, comes from the inner bark of holly mistletoe or elm branches, boiled, then evaporated, to form a sticky substance, used to trap small birds.
Its use is illegal in many countries.
Birdlime is not "lime", calcium oxide.
The latex of breadfruit was formerly used as birdlime to catch birds by people in the South Pacific region.

Brass
Brass Experiments
Brass is mainly alloys of Cu and Zn, but Al, Fe, Mn, Ni, Sn, and Pb may be added.
Brass filings Local Purchase

Bronze
Bronze Experiments
Bronze is mainly alloys of copper and tin, but some bronze may not contain tin, e.g. aluminium bronze, manganese bronze, and the bronze in "copper" coins.
The first bronze made in the ancient world was probably copper combined with arsenic, and may have been quite toxic.

Bottled gas, compressed gas
Bottled gas is gas in metal cylinders under pressure e.g. O2 and N2, and gas liquefied under pressure e.g. (C4H10).
UK standard colours on cylinder shoulders, (EN 1089-3):
black (N2), blue (N2O), brown (He), dark green (Ar), grey (CO2), light blue (oxidizing gas), maroon (C2H2), red (flammable gas), white (O2), yellow (toxic gas and corrosive gas).
See the internet for colours in your country e.g. EU Compressed Gas Cylinder colour codes.

Buffers
Buffers: 7.4.14
Buffer reagent, phosphate buffer reagent: 9.2.25
Buffers, food buffers, food additives: 19.4.12
Food buffers, adipic acid, food acid: E355
Prepare buffer solutions: 12.10.7.0
Buffer solutions tablets, pH 4, pH 6.4, pH 8, pH 9.2
Aluminium ammonium sulfate, food additive, E523, buffer stabilizer
Buffer ampoules, 1000 mL, pH 7.0, pH 8.0, pH 9.0, pH 10.0
Buffer solution, 500 mL, colour coded for pH 10.0, pH 9.0, pH 7.0, pH 4.0 pH 10.5
Buffer solutions, pH 10, Colour coded blue
Buffer solutions, pH 4, Colour coded red
Buffer solutions, pH 7, Colour coded yellow
Buffer tablets, pH 4.0.
Buffers
A buffer or buffer solution is a mixture of substances that tend to hinder large changes in acid or basic properties of a solution.
The term "buffer" is used in a more general sense outside chemistry.
The pH of a buffer solution is not greatly changed by the addition of an acid or an alkali.
Most buffer solutions are a mixture of a weak acid or base with one of its salts.
In body fluids, the buffers include (H2CO3) with (HCO3 - ).
Acidic buffer, e.g. sodium hydrogen carbonate with carbonic acid solutions, the salt of the weak acid is completely dissociated into ions, but the weak acid is only partly dissociated.
Basic buffer, e.g. ammonium chloride in ammonia solutions.

Butane gas, C4H10
Butane gas, Experiments
Butane gas, (C4H10), 93.2 MJm -3 , a liquefied petroleum gas (LPG), liquefied gas, bottled gas, is liquefied butane, Calor gas.
Butane isomer is 2-methylpropane, [CH3CH(CH3)CH3], formerly called "isobutane".
A mixture of butane and 2-methylpropane is used in disposable cigarette lighters.
2C4H10 (g) + 13O2 (g) --> 8CO2 (g) + 10H2O (g).

Cellophane
"Cellophane" is the trade name for a glossy transparent wrapping material.
Modified cellulose (cellophane is a trade name from: cellulose + (French diaphane transparent).
cellulose + alkali + carbon disulfide --> viscose through sulfuric acid and sodium sulfate --> cellulose + glycerine --> cellophane rayon.
Cellophane is used in food and cigarette packages, "Sellotape", "Scotch Tape", dialysis tubing, (Visking tubing).
See: Dialysis, (Commercial)

Coal gas
Coal gas, (approximately 88 MJ / kg), is approximately 50% hydrogen gas, 35% methane, 8% carbon monoxide (poisonous gas), hydrogen cyanide and hydrogen sulfide (for a "safety smell").
Lately, "synthetic natural gas", SNG, is synthesized from coal or petroleum.

Cobalt chloride
Cobalt (II) chloride, (CoCl2.6H2O), cobaltous chloride, cobalt (II) chloride hydrated, cobalt (II) chloride-6-water, cobalt chloride hexahydrate, harmful if ingested, environment danger, hydrated salt, pink-dark red, deliquescent crystals, pink powder, acidic solution, CoCl2 (anhydrous salt blue test for water humidity paper in silica gel desiccant), blue borax bead.

Collagen
Protein in animal connective tissue, boiled to make gelatine glue, insoluble fibrous protein in connective tissue, polypeptide, chain mainly glycine, and proline gristle used for sausage casings.

Collodion
Solution of pyroxylin, (inflammable solution of nitrocelluloses), in ether to make a thin sticky film.
Cellulose nitrate, nitrocellulose, dissolved in a mixture of ethanol or diethyl ether.
Cellulose tetranitrate used as a surgical dressing or medicinal coating.
Collodion was used in an early photographic process, cellulose nitrate + soluble iodide coats a glass plate, then in darkroom, immersed in silver nitrate to form silver iodide, then the wet plate was exposed in a camera, then developed with pyrogallic acid and fixed with sodium thiosulfate or potassium cyanide solution.

Copper (II) acetoarsenite, Paris Green, (C2H3AsCuO4)
Copper (II) acetoarsenite, [copper ethanoato-arsenate copper (II) acetate triarsenite], Emerald green, Paris Green, Schweinfurth Green, is a double compound of copper arsenite, (Scheele's Green), and copper acetate, (verdigris), [Cu(C2H3O2)2.3Cu(AsO2)2] bright yellow-blue-green pigment, still used as a poison, and for green colour in fireworks, agricultural chemical, wood preservative, and ship anti-fouling application.
However, it is very poisonous, and nowadays is thought to be too dangerous to use.
Its use in wallpaper may have killed the exiled Emperor Napoleon Bonaparte on St. Helena Island!
It is very poisonous and nowadays is thought to be too dangerous to use.
Highly toxic pigment.
Copper (II) arsenate, [Cu3(AsO4)2.4H2O], [Cu5H2(AsO4)4.2H2O]
Copper arsenite, (AsCuHO3), (CuHAsO3), copper (II) arsenite, cupric arsenite, Scheele's green pigment, Paris green, emerald green, copper arsonate, Swedish green, cupric green, air-flo green, acid copper arsenite, green, acidic copper arsenite, pigment of significant toxicity.

Corn oil, maize oil
5.5.0.0 Maize, (Zea mays, Indian corn)
Corn oil, maize oil, made from germ of maize grain for salads
Use corn oil to moisturize skin, add to bath water, prevent cat hair balls, condition human hair or dog's coat, and remove dirt, remove oil paint or sap from skin, prepare and remove rust from cast iron skillets and barbecue grills, lubricate hinges, remove furniture marks and glue, coat snow tools, remove decals, oil for wooden implements and tools, soothe sore skin, use before removing wood splinter, soften new boots, remove price tags and paper stuck to wood, treat ear mites in cats and treat human ear wax.

Cornstarch
Use cornstarch powder for baby powder vacuum cleaning inside rubber gloves and shoes dry dog shampoo toy stuffed animals, remove excess furniture polish grease and oil stains cutting boards rolling pins.
Use cornstarch to thicken gravy.
Use cornstarch paste for skin irritations and sunburn pain, blood stains, car shining, knot untangling, finger paints (+ colouring), and to clean silverware.
Use cornstarch + plaster of Paris to kill cockroaches, when they eat the mixture.

Crayons
The crayons used by children for drawing and colouring are usually sticks of coloured wax, but artist's crayons may be made of charcoal, chalk, oiled chalk (called an "oil pastel"), pigment with dry binder (called a "pastel").
Crayon marks made by naughty children can be removed with white toothpaste.
Use crayons to remove grease from collars and clothing, absorb moisture, in small boxes, make a non-slip tip to screwdriver, polish marble and metal repair hole in plaster wall.

Creosote
Cresol mixture: (2-hydroxytoluene 3-hydroxytoluene 4-hydroxytoluene), sensitizes skin to sunlight, use gloves.
Wood creosote is mixture of phenols of wood tar.
It is used as a disinfectant, cough medicine, diarrhoea medicine, preservative, antiseptic.
Coal tar creosote is used as a wood preservative, fungicide, insecticide and for treating skin diseases, but may cause skin cancer.
Creosote (prohibited substance for schools)
Coal tar products, creosote: 16.2.10

Cresols
Cresols are methyl phenols C7H8O, CH3(C6H4)OH, produced from coal tar creosote or by methylation of phenol.
"Cresol" used as a disinfectant is usually a cresol mixture: o-cresol, m-cresol, p-cresol.
Cresols are Toxic by all routes.
Cresols, C7H8O or CH3C6H4OH, have a methyl group substituted onto the ring of phenol.
Cresols can be extracted from coal tar or produced methylation of phenol.
Cresols are flammable and have ingestion and inhalation toxicity.
Cresols are colourless, but yellow-brown with age, and with a "coal tar"or phenol-like odour.
Three isomers of cresol:
1. Ortho-cresol, o-Cresol, (2-Methylphenol), (2-hydroxytoluene), (2-Cresol), phenol substituted by a methyl group at position 2 corrosive, acute toxic, colourless to brown-yellow to pink liquid, colourless crystals, insoluble in water, commercial disinfectant.
2. Meta-Cresol, m-Cresol, (3-methylphenol), (3-hydroxytoluene), (3-Cresol), liquid. metacresol purple, C21H18O5S, phenol substituted by a methyl group at position 3, thick liquid, highly toxic by all routes, but solution < 12%, Not hazardous.
m-cresol purple sodium salt, C21H17NaO5S.
3. Para-cresol, p-Cresol, (4-Methylphenol), (4-hydroxytoluene), (4-Cresol), phenol substituted by a methyl group at position 4, colourless greasy solid, sinks and mixes slowly with water.
Cresol compounds
Cresol red, (C21H12NaO5S)
Cresol red, o-cresolsulfonephthalein: 12, (indicator)
Cresol red sodium salt, (C21H17NaO5S): 12.1
Cresols: 16.1.3.2.3
o-Cresolsulfonephthalein, triarylmethane dye, acid-base indicator, used to monitor pH in aquaria, irritates eyes, do not ingest.
See diagram Cresol
Prepare cresol red indicator solution: 12.0.
Prepare cresol red, Na salt, indicator: 12.1.

Cresyl, CH3C6H4O-
Cresyl violet acetate, (C18H15N3O3), 9-Amino-5-imino-5H-benzo[a]phenoxazine acetate salt, stains neurones
Cresyl violet perchlorate, (C16H11N3O.HClO4), oxazine 9 perchlorate, biological stain
Cresylic acid, CH3C6H4OH, "cresol"

Cresylic acid, cresols
See 16.1.3.2.3: Cresols
Cresylic acid is a mixture of coal tar or petroleum byproduct phenols, disinfectant, Highly toxic by all routes.
(CH3C6H4OH), cresol, (mixed isomers), coal tar acids, coal tar cresols, coal tar phenols, methylphenol mixed, crysylol, hydroxytoluene cresol all isomers, tricresol, methylphenol, mixed cresols.
Cresylic acid, Solution < 3%, Not hazardous
Cresylic acid compounds are called "cresol" when the boiling point is below 204 o C.
Cresols are mixtures of the ortho-, meta- and para- isomers.
Crude cresol contains approximately 20% o-cresol, 40% m-cresol, and 30% p-cresol.
Amber to red colour.
Cresols are used to manufacture synthetic resins, as degreasing compounds, paintbrush cleaner, fumigants in photographic developers, and explosives.
Any combustion process that results in the generation of phenolic compounds, e.g. exhausts from motor cars, coal, wood, or trash smoke, may be a potential source of exposure to cresols.

Crude oil
Petroleum distillate oil, unrefined natural petroleum.

Cyanuric acid<, (CNOH)3
Cyanuric acid, (CNOH)3, (H3C3N3O3), is used in for swimming pools, purifying tablets, white soluble crystals, solution converts to urea.

DMSO, (CH3)2SO
Dimethyl sulfoxide, (CH3)2SO, (C2H6OS), from wood pulp, oyster garlic taste, (irritant, penetrates skin, horse liniment, anti-inflammatory, paint stripper

Desiccants
Drying agents, e.g. anhydrous calcium chloride, anhydrous calcium sulfate, concentrated sulfuric acid, phosphorus (V) oxide, sodium hydroxide lump, calcium oxide lump (lime), silica gel.
Glass desiccators used to dry chemicals in the laboratory may have tap in the lid to increase evaporation by decreasing pressure in the desiccator.
Glass desiccators can also preserve organic materials by desiccation.

Gases
Bottled gas compressed gas LPG LP Gas
Butane gas
Coal gas
Household gas
Laboratory gas, piped gas
LPG (liquefied petroleum gas LP gas)
Methane gas
Natural gas
Producer gas
Propane gas
Town gas
Watergas

Gelatin, gelatine
Amorphous, yellow to colourless, transparent, tasteless, material, brittle when dry, from collagen protein produced by boiling animal tissues, e.g. skin and ligaments, used in glue, jelly crystals, e.g. puragel, photographic emulsions, adhesives.
Also, gelatin dynamite and blasting gelatin, underwater explosives, containing nitroglycerine and cellulose nitrate.

Glass wool
Glass wool, Irritant, (glass wool, silane-treated)
Glass wool is not recommended for use in school laboratories.
Students should not handle glass wool.
Thin pieces of glass wool can get into cuts and then into the bloodstream.
Do not touch glass wool with the fingers, wear protective gloves.
Do not breathe in glass wool fibres.
Teachers and laboratory assistants may use glass wool in the preparation room, but they should wear an appropriate respiratory mask.
Do not reuse damaged glass wool, because it may release glass fibre particles into the air.
Glass wool is sold as "Glass wool for laboratory use", with suggestions for eye shields, gloves and respirator filters.

Glazes
Pottery glazes were formerly metal oxides, e.g. lead oxide and cadmium oxide, often heavy metals, but most glazes nowadays have the metal oxide fired with silica to form sintered glass.
Glazes for school use must contain no cadmium and < 0.1% lead dry weight.
Glazes are sold as "school glazes."

Glycogen, (C6H10O5)n
Glycogen, (C6H10O5)n, animal starch, liver starch, is a branched polymer of glucose synthesized by animal cells for energy storage.
Glycogen is constructed mostly of (α14) glycosidic bonds with branches created through α16 glycosidic bonds.
Glycogen is usually prepared for sale from rabbit liver and from Mytilus edulis, (Blue mussel).

Hair
Keratin is a fibrous protein occurring in hair, wool, feathers, hooves and horns, imbedded in a matrix that makes them strong and elastic.
The proteins contain sulfur and are held together by disulfide bonds.

Inks
Inks include solvent-based ink, water-based ink, ball pen refill, "Biro" or "Bic" refill, Indian ink, variable toxicity, solvent may be flammable, marbling ink.
Students must not ingest marbling ink used in primary schools.
Indian ink, (Chinese ink), is a mixture of lampblack, carbon black, bone black.
For block printing and screen printing, do not use oil-based solvents, but use water-based screen printing inks, e.g. "Lascaux".

Invertase
Invertase from baker's yeast, is a yeast extract enzyme.
It catalases sucrose hydrolysis to fructose and glucose, (invert sugar).
Invertase is harmful if ingested, irritates eyes, food additive (E1103).
It is used as a stabilizer, a food processing aid, and in the production of confectionery foods and artificial honey.
Invertase hydrolyses sucrose into glucose and fructose, yielding a colourless product, unlike acid hydrolysis of sucrose, which produces coloured products.
Invertase is sold as "Invertase from baker's yeast (S. cerevisiae), practical grade".

Investigation
"The process of examining or inquiring into something with organization, care and precision." Queensland Studies Authority.

Iodine monochloride
Iodine monochloride, ICl, Wijs' solution, Tests for fats and oils
Wijs' solution, iodine chloride, iodine monochloride, Toxic by all routes, avoid vapours, brown-red crystals.
Iodine monochloride is dissolved in acetic acid to form Wijs' solution to test fats and oils for the iodine value or iodine number to determine the degree of unsaturation in fatty acids, e.g. coconut oil about 9, olive oil about 85, linseed oil about 200.

Isocyanuric acid
Isocyanuric acid, tricarbamide, s-triazinetriol, (C3H3N3O3), is a chlorine stabilizer for swimming pools, administered as sodium dichloroisocyanurate granules or trichloroisocyanuric acid tablets.

Javelle water
Aqueous solution of potassium or sodium hypochlorite, used as a disinfectant and bleaching agent.

Laboratory gas
In a laboratory, the pilot light should burn with a 90% blue flame.
If the flame is yellow, the gas may be contaminated with condensates.
Do not use such a gas, but immediately inform the local gas authority.
The heating values of fuels: town gas 88 MJ / kg, natural gas 55.6 MJ / kg, LPG gas 49 MJ / kg, diesel fuel oil 38 MJ / L, kerosene 36.7 MJ / L, coke or coal 27 MJ / kg, dry split wood 12.5 MJ / kg.

Lavender oil
Lavender flower oil, mainly | Linalyl acetate | from Lavandula latifolia, (insect repellent, dog inhibitor, air freshener, pain relief)

Lemon juice, lemon oil
Use lemon juice to treat dandruff, blackheads, facial blemishes, rough hands, sore feet, constipation, itches, minor wounds, with honey and olive oil relieve coughing, unclog ketchup bottles, write with invisible ink, blonde hair, deodorize cooked fish, cutting boards, fish cooking utensils, microwave ovens and refrigerators, remove fruit stains, rust, mineral discoloration, ink spots from clothing, whiten fingernails, with salt clean brass and stainless steel sink.
Use lemon juice to prepare bathtub rust stains cleaner.
Lemon oil is oil from lemon peel | Limonene | a terpene, used for furniture polish, inhibits spiders and insects, stain remover.

Light oil, sewing machine oil
Sewing machine oil, WD-40 penetrating oil to prevent corrosion.
The contents of WD-40 are a commercial secret, but it is said to contain Paraffin, white spirit, mineral oil, lubricating oil, transformer oil, vacuum pump oil, dimethyl naphthalene, carbon dioxide.

Linseed oil
From seeds of flax, Linum usitatissimum, glycerides of oleic acid and other unsaturated acids.
Used to condition and seal bare wood in putty, paints, varnishes, for cricket bats, linoleum, outdoor furniture.

Liver of sulfur
Alkaline mixture of mainly potassium polysulfides that turns silver black.

LPG, Liquefied Petroleum gas, LPG, LP Gas, Liquefied Petroleum gas, is a clean burning fuel and is stored in gas cylinders as bottled gas.
LPG is a simple asphyxiant.
It consists of propane, (about 95%), together with varying proportions of butane, propylene and butylene.
A rank smelling compound, odorant, e.g. ethyl mercaptan, is added so that the presence of the gas can be easily detected.
Incomplete combustion forms carbon monoxide.
Do not search for a gas leak with a lighted match or lighted taper.
Use a soap solution.
Highly flammable, violently explosive mixture with air, toxic if inhaled, purchased as cylinders containing the liquefied gas.
Fill cylinders by weight only.
Hazchem Code 2YE.
UN number 1075. Keep container upright in a well-ventilated place away from sources of ignition.

Magnesium ribbon
Magnesium powder is too dangerous for school use.
Magnesium powder dispersed in air is explosive and may explode on contact with oxidizing agents, e.g. metal nitrates or chlorates, and should not be combined with carbon tetrachloride, carbon dioxide, chlorinated hydrocarbons, halogens.
Magnesium ribbon is easily ignited and burns very exothermically almost instantaneously, with a white hot flame that emits UV radiation and may cause eye damage.
Use < 1 cm of magnesium ribbon in experiments.

Re-lighting candles
Re-lighting candles, (happy birthday candles which you can't blow out!), "Trick Candles", "Magic Candles".
The relatively low autoignition temperature, 473 o C, is used in trick happy birthday candles that cannot be blown out.
When a candle is blown out a glowing ember usually remains in the wick , but it does not provide enough heat to ignite the paraffin.
The wicks of trick candles contain particles of magnesium powder, which may be ignited by the glowing ember to then ignite any remaining paraffin vapour.
Look closely at the wick of a trick candle just before it reignites to see sparks of burning magnesium powder.
Only the magnesium in the glowing ember ignites, so the trick candle can be blown out then reignites many times, because the magnesium in the rest of the wick does not burn, being isolated from the air by the liquid paraffin.
Extinguish the trick candles by putting them in water.
Put away for the trick candle for storage only after several minutes and be sure that they are extinguished.
The wicks of re-lighting candles should be < 6 mm.

Metaldehyde
Metaldehyde is an ethanal tetramer formed by polymerization of ethanal, acetaldehyde, (CH3CHO)4) --> [C4O4H4(CH3)4], "meta" fuel, fire lighter, canned heat, snail bait, "Esbit", "Blitzem".

Metglas
Metglas is a ribbon of an alloy, e.g. iron, boron silicon, phosphorus, formed by very rapid solidification.
It is used for joining metals by braising, transformer cores, and in pulse power switches.
Metglas can be rapidly magnetized and demagnetized.
For example, Powerlite C-Core, an iron-based Metglas, has low loss and high saturation flux density compared to other ferromagnetic materials.

Methane gas
Methane gas, (CH4), natural gas, (55.6 MJ / kg), marsh gas.
Natural gas is flammable gas, 99% methane, occurring naturally underground, usually associated with petroleum.
CH4 (g) + 2O2 (g) --> CO2 (g) + 2H2O (g) + heat.
Methane is large proportion of coal gas, (firedamp in coal mines, methane burns to form air depleted of oxygen, called blackdamp, choke damp).

Natural gas
(CH4), (C2H6), (C3H8)
It occurs usually over petroleum products so its composition varies.
Natural gas usually contains about 90% methane + various proportions of ethane, propane, butane, nitrogen and carbon dioxide.
It is odourless, but during manufacture a rotten egg rank smelling compound, e.g. a mercaptan, captan, (ethane thiol or ethyl mercaptan), may is added for gas detection.
Incomplete combustion produces carbon monoxide.
It should burn with a 90% blue flame.
Natural gas is used in heating and cooking appliances, buses and other motor vehicles and is transported by large tankers or gas grids.
In many places it has replaced town gas.
Safety procedures:
1. Check the colour of the flame in the pilot light is yellow.
If a yellow condensate forms on the nearby wall or the bottom of cooking pots have a black smudge, ask the gas distribution authority for advice, because the gas may be contaminated.
2. Gas leaks
Cover a suspected gas leak with a soap solution.
If any bubbles form in the solution, contact the gas distribution authority and report a gas leak.
Be careful! Do not search for a gas leak with a lighted match or lighted taper, but use a soap solution.
3. Regularly check all equipment using natural gas.
Use sturdy undamaged tubing to connect Bunsen burners to gas taps.
Replace any perished tubing or tubing damaged at one end.
Check that tubing is connected securely to both the tap and the Bunsen burner before the gas is turned on.
5. Clean or replace any Bunsen burners that have damaged jets, or are known to burn back (strike back).
6. At the end of the school day, turn off the master gas switches in each laboratory.
7. Do not allow dangerous practices, e.g. turning on a gas tap and then lighting it.
8. If you smell an overpowering gas odour in a laboratory, evacuate the area rapidly, open all windows and seek assistance.

Paraffin oil, kerosene
Paraffin, hard paraffin wax, (chunks), alkane mixture, (CnH2n+2), paraffin wax black 43 / 46
The term "paraffins" was the former name for "alkanes".
Paraffin, (Latin parum little, affinis connected), because of its low chemical activity.
The name invented by German chemist Karl Reichenbach in 1830.
1. Paraffin, fp 60 o C, (UK, paraffin oil), (USA, Australia, kerosene), (also kerosine, "kero"), is a petroleum fraction containing a mixture of about ten different hydrocarbons, 10 to 16 carbon atoms per molecule, depending on the origin of the original petroleum.
Its flash point, temperature to form flammable vapour, is 38 o C, so it is a relatively safe fuel.
Use paraffin oil, kerosene, in a well-ventilated space for kerosene lamps and domestic heaters, but do not use it as a degreaser of engines.
2. Paraffin wax is alkanes, (C20H42) to (C40H82), and is used to make candles, polish, "wax" paper.
3. Liquid paraffin, (petrolatum liquid, paraffin liquid), is a pure mineral white oil emulsion used as a medicine.
It is a colourless, tasteless, liquid form of petroleum jelly, mixture of >C12 alkanes, known a petrolatum jelly, ("Vaseline", trade name) White paraffin, is another kind of petroleum jelly.
Paraffin wax, has mp 45 to 65 o C, (sold as pastillated wax, 52 o C), relative density 0.9.

Pennyroyal
Pennyroyal, (Mentha pulegium), European pennyroyal, squaw mint, mosquito plant, pudding grass, pouliot, pulegium, pungent, pepper tasting, culinary herb, herbal medicine, abortifacient, but pennyroyal oil is poisonous, liver toxicity, Lamiaceae.
Perennial, dicotyledon, grows up to 50 cm tall with smooth roundish stalks and aromatic, grey-green oval leaves, lilac flowers in distinct whorls in late summer and autumn, fibrous creeping root.
Used for ground cover, rockeries and paths when walked on releases refreshing peppermint, strong fragrance, culinary uses, to flavour root vegetable, infusions as pet rinse to deter fleas. Europe, Middle East.
Pennyroyal oil, herbal medicine for temporary relief of headaches and cramps, (not during pregnancy).
However, it is toxic and an abortifacient and can even in small quantities cause acute liver and lung damage.
Pennyroyal oil should not be used in aromatherapy.
Formerly it was used to "purify the blood", and for digestive and menstrual problems and feverish colds.
It is an effective insect repellent and deters ants, fleas, flies and moths.
The main chemical components of pennyroyal oil are pulegone, menthone, iso-menthone and neomenthone.
Dried herb sold as aerials.

Producer gas
Air gas.
Similar to water gas, formed by passing air and steam over hot carbon.

Propane gas
Propane gas, (C3H8), a bottled gas, a liquefied petroleum gas, (LPG).

Resin
Ion exchange resin
Anion exchange resin, zeolite, ("Permutit")

16.14.4 PFAS chemicals
PFAS, Australian Government
PFAS, or per- and polyfluoroalkyl substances, is the broad name for 4,700 chemicals that do not break down, and instead accumulate in the soil, water, and human bodies.
1. (CNN) PFAS chemicals are known as “forever chemicals,” a family of potentially thousands of synthetic chemicals that are extremely persistent in the environment and in our bodies.
PFAS is short for perfluoroalky and polyfluoroalkyl substances and includes chemicals known as PFOS, PFOA and GenX.
They are all identified by signature elemental bonds of fluorine and carbon, which are extremely strong and what make it so difficult for these chemicals to disintegrate in the environment or in our bodies.
PFAS chemicals have been highly utilized in various industries, because of their ability to repel oil and water.
They’ve been manufactured since the 1940s and can be found in Teflon nonstick products, stains and water repellants, paints, cleaning products, food packaging and firefighting foams.
A growing body of science has found that there are potential adverse health impacts associated with PFAS exposure, including liver damage, thyroid disease, decreased fertility, high cholesterol, obesity, hormone suppression and cancer.
These chemicals can easily migrate into the air, dust, food, soil and water.
People can also be exposed to them through food packaging and industrial exposure.
Emergency response teams hand out free bottled water to residents at the Parchment High School in Parchment, Mich., Friday, July 27, 2018.
Authorities handed out thousands of free bottles of water Friday for two southwestern Michigan communities where the discovery of contamination from toxic industrial chemicals prompted a warning against using the public water system for drinking or cooking. (Daniel Vasta/Kalamazoo Gazette via AP)
“I think that people should be concerned about the amount of PFOA and PFOS that is in our environment,” Susan M. Pinney, a professor in the Department of Environmental Health at the University of Cincinnati, US, wrote in an email.
“These are chemicals with long half-lives,” meaning they persist in the environment as well as the body.
They can also accumulate over time.
In the body, they primarily settle into the blood, kidney and liver. A study from 2007 by the US Centers for Disease Control and Prevention estimated that PFAS chemicals could be detected in the blood of 98% of the US population.
“Exposure in utero may have the greatest effect on developing children … and effects may last into adulthood,” Pinney said, adding that the science is still early.
PFOS and PFOA are the two most-studied PFAS chemicals and have been identified as contaminants of emerging concern by the Environmental Protection Agency.
2. (ABC) The Australian federal government has settled a class action over PFAS contamination from firefighting foam at seven sites across the country, but residents are calling the amount "atrocious".
About 30,000 claimants will be paid $132.7m from the Commonwealth over historic contamination of regional towns.
The settlement follows a $212m PFAS payout for property value loss and distress in Katherine, Oakey, and Williamtown.
PFAS is a broad name for 4,700 heat-resistant chemicals that were found to be toxic in groundwater near air force bases.
The Commonwealth Government of Australia will pay out $132.7 million to about 30,000 claimants.
The claim alleged landowners at the sites were exposed to poisonous chemicals in firefighting foam used at military bases after it leached into groundwater.
The sites are Wagga Wagga and Richmond in New South Wales, Wodonga in Victoria, Darwin in the Northern Territory, Townsville in Queensland, Edinburgh in South Australia, and Bullsbrook in Western Australia.
Perfluoroalkyls are stable, synthetic chemicals which repel oil, grease, and water.
They have been used in surface protection coatings for carpet, clothing, paper, cardboard packaging, and in fire-fighting foams.
The largest amounts made in the US are perflurooctanoic acid, (PFOA), and perfluorooctanesulfonic acid, (PFOS).

16.14.1 PBDE, pentabromodiphenyl ether, C12H5Br5O
PBDE, pentabromodiphenyl ether, (C12H5Br5O), PBB, polybrominated biphenyls, 4,4'-dibromobiphenyl, (C12H8Br2)
PBDE consists of two benzene rings linked with an oxygen atom, instead of hydrogen, and up to 10 bromine atoms may be attached to the benzene rings.
For flame protection the congeners are 5 to 10 bromine atoms.
PBB consists of two directly linked benzene rings, and up to 10 bromine atoms.
PCB is a partly volatile liquid while the current flame retardants are solid with very low volatility.
Both PBDE and PBB are additive substances, i.e. without chemical reaction they are mixed with materials to be anti-inflammable.
Like the corresponding chlorinated substances, can develop dioxins and furans (polybrominated dibenzodioxins and polybrominated dibenzofurans) in case of incomplete combustion.
Some of the corresponding chlorinated substances have a very high toxicity as well as being carcinogenic.
The toxic effects of brominated dioxins and furans are not known.
PBB has been detected in human milk.
Many PBDEs have been banned in many countries.

16.14.2 PFOA, Perfluorooctanoic acid, C8HF15O2
Perfluorooctanoic acid, (PFOA), (C8HF15O2), a surfactant, is used to make non-stick cookware, e.g. PTFE, ("Teflon"), and stain-resistant footwear and clothing.
It persists in the environment and is toxic to animals and may be a carcinogen.
Long-chain perfluorinated chemicals, LCPFCs, are very persistent in the environment and are found in the blood of the general U.S. population and in human milk.
PFOA is used to make fluoropolymers, e.g. polytetrafluoroethylene (PTFE).
Teflon^TM is not a specific chemical or product.
Perfluorooctanoic acid (PFOA), is used in the process of making Teflon and similar fluorotelomers, but it is burned off during the process and is not present in significant amounts in the final products, e.g. non-stick cookware.
Some major manufacturers have agreed to eliminate the use of PFOA by 2015.
They are increasingly linked to cancer, liver and thyroid disease, immune suppression and reduced fertility.
Fluoroform (CHF3)
Tetrafluoroethene (CF2CF2), Teflon
Polytetrafluoroethene (PTFE, Teflon), poly(1.1.2,2-tetrafluoroethylene), Repeat unit: -[CF2=CF2]n-), (C2F4)
"Teflon" is a synthetic fluoropolymer of tetrafluoroethylene.

16.14.3. PFOS, perfluorooctanesulfonic acid, C8HF17O3S
Perfluorooctanesulfonic acid (PFOS), man-made fluorosurfactant and global pollutant was the key ingredient in Scotchgard, a fabric protector and different stain repellents.
PFOS was added to Annex B of the Stockholm Convention on Persistent Organic Pollutants in May 2009, so it is banned under international environmental treaties.
In Australia, June 2016, residents of the town of Oakey have received assistance from an AUD 55 million dollar government assistance to fund blood testing and counselling, fearful of contamination from PFOS and PFOA fire fighting chemicals used at the Oakey Army Aviation Base, southern Queensland. Residents are also asking for a government commitment to buying back contaminated land or adequate compensation.
These chemicals have also been found at Brisbane Airport and close to the Williamtown RAAF base, near Newcastle.
They are increasingly linked to cancer, liver and thyroid disease, immune suppression and reduced fertility.
Australian health protection drinking water guidelines of 0.5 micrograms per litre for PFOS and 5 micrograms per litre for PFOA are said to be above the 0.07 micrograms per litre adopted by the US.
In addition to industrial production, PFOS can form from the degradation of its precursors.
PFOS levels detected in wildlife are thought to be high enough to affect health parameters, and higher serum levels of PFOS are associated with increased risk of chronic kidney disease in the U.S.

16.14.6 Erucic acid, C22H42O2
Erucic acid, 13-docosenoic acid (C22H42O2), monounsaturated omega-9 fatty acid, very long chain 22-carbon backbone and single double bond, in Brassicaceae oils, often with bitter-tasting compounds, used as transmission oil, because high tolerance to temperature, readily bio-degradable, binder for oil paints, in mustard oil, in rapeseed oil, but not in canola oil.
Babies should not be given foods high in erucic acid.