School Science Lessons
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Chemistry G
Table of Contents
Gadolinium, Gd
Galacturonic acid
Galangin, C15H10O5
Galanthamine, C17H21NO3
Galegine, plant amine
Galena, PbS, lead glance: 35.20.15
Gallic acid, C6H2(OH)3COOH:
Gallocyanine, Tests for antimony:
Galvanic cell, Voltaic cell: 33.84.1
Galvanic Series:
Galvanized iron, galvanized steel
Gamma carotene, Vitamin A:
Gamma radiation, Radiation, ionizing radiation, Geiger counter: 2.9.0 (See: 3.)
Gammexane, Lindane: 16.3.3
Garlic, Sulfides:
Garlic spray: 16.9.2 (Agriculture)
Garnet: (Geology)
Gas, gases
Gasoline, "gas", Distil crude oil and collect the fractions: 10.6.3
See: Gauze Mats (Commercial)
Gels, gelatine, gelatin
Gelsemicine, alkaloid
Gentamicin, C21H43N5O7
Gelatine, Cooked collagen changes into gelatine.
Gentianose, Oligosaccharides
Genetic code
Genistein, C15H10O5
Gentian violet 10B, C25H30ClN3, crystal violet
Gentianadine, alkaloid
Gentianaine, alkaloid
Gentianine, alkaloid
Gentiobiose, Oligosaccharides
Gentioflavine, alkaloid
Gentiopicrin, C16H20O9
Gentipicrocide, C16H20O9
Geology, Earth Science: 35.0.0
See: Geology (Commercial)
Geosmin, C12H22O
Geranic acid, C10H16O2
Geraniol, C10H18O
Geranyl acetate, C12H20O2
Gerber butterfat test: 16.1.7
Germ cell mutagenicity: 5.4
German silver, alloy
Germacrene, C15H24
German silver, silvery-looking cheap alloy of copper, zinc and nickel.
Germanium, Ge
Ghee, Butter, butter oil, clarified butter: 16.2.3
GHB, C4H8O3, 4-hydroxybutanoic acid: 12.2.1
Ghost crystals, Prepare sodium polyacrylate gels:
GHS, Globally Harmonised System of Classification
Gibberellins:, (Agriculture)
Giemsa stain, Prepare Giemsa stain : 3.28
Ginger beer "plant": 9.212
Gingerol, C17H26O4:
Ginsenoside RG1, C42H72NO14
Glacial acetic acid, acetic acid, CH3COOH (pure acid called "glacial'!)
Glasses, Safety glasses
Glauber's salt, Sodium sulfate, Na2SO4.10H2O
Glaucarubin, C25H36O10
Glaucine, alkaloid
Glaziovine, alkaloid
Glazes (pottery glazes)
Glazing agents, food additives: 19.4.19
Globular proteins, Fibrous proteins and globular proteins:
Gloves, Protective clothing and equipment: 3.2.2 (Safety)
See: Gloves (Commercial)
Glowing splint test, Tests for oxygen gas: 3.49.1 (See: 1.)
Glucan (C6H10O5)n
Glucinium, Beryllium, Be
Glucobrassicin (C16H19N2O9S2)
Gluconic acid, C6H10O7
Gluconobacter, Make wine from grape juice and vinegar from wine: 4.2.4
Glucoronic acid, C6H10O7, derived from glucose
Glucoronic acid-1-phosphate, C6H11O10P, uronic acid phosphate
Glucose, C6H12O6
Glucuronic acid
Glues and pastes, Prepare glues and pastes, adhesives, gums: 9.0
See: Glue, (Commercial)
Glutamic acid, C5H9NO4, (Table of amino acids)
Glutamic acid, DNA codons
See: Glutamic Acid (Commercial)
Glutamine, C5H10N2O3, (Table of amino acids)
Glutamine, DNA codons
Glutaraldehyde solution, microscopy fixative: 4.20
Glycaemic index (GI): 4.2.11
Glyceraldehyde, C3H6O3
Glyceric acid, C3H6O4, 2, 3-Dihydroxypropanoic acid, α-hydroxy acid
Glycerine, C3H8O3
See: Fat Glyceryl tristearate, model, (Commercial)
Glycinate (Gly), amino acid, NH2CH2COOH, bidentate ligand
Glycine, H2CH2COOH
Glycoalkaloids: 16.3.28
Glycogen, C24H42O21
Glycols, dihydric alcohols:
Glycolic acid, hydroxyacetic acid, HOCH2COOH, α-hydroxy acid
Glycoproteins, Conjugated proteins: 16.3.16
Glucoraphanin (C12H23NO10S3)
Glycyrrhizin, C42H62O16, saponin
Glyoxal-bis(2-hydroxyanil), C14H12N2O2, metal titration indicator, calcium red, GBHA
Glyphosate, C3H8NO5P, herbicide: 16.7.3
Glycosylated haemoglobin test, Tests for glucose: 8.0
Goanna oil, from goanna fat, lizard-like Varanus sp (lubricant, liniment, arthritis, muscle soreness)
Goethite, FeO(OH) (Mineral)
Gold, Au
Gossypol, C30H30O8
GR (Guaranteed Reagent), chemicals standards
Gram stain, Prepare Gram stain: 3.11.0
Gramine, plant amine
Gram's iodine solution, Prepare Gram's iodine solution: 1.6.2
Granisetron, C18H24N4O (5HT3 antagonist), prevents nausea of cytotoxic drugs, surgery, radiotherapy
Granite: 35.21.2 (Geology)
Granules:, (Agricultural chemicals)
Granules, Anti-bumping granules, boiling chips: 7.9.12
Granules, Boiling point of liquids: 7.5.0
Grape seed oil, Composition of edible oils: 19.2.11 (Table)
Grapefruit mercaptan, C10H18S, thioterpineol
Graphene, C, atom-thick layer of carbon atoms, flat lattice of hexagons, has field effect like silicon
Graphite, C: 35.41.3
Graphs: 4.1.0
Gravimetric analysis: 17.6.0
Green hair and faded hair from swimming pools:
Greenhouse gases
Greek alphabet
Greenockite, CdS, cadmium sulfide (Mineral)
Greigite, Fe3S4, iron (II, III) sulfide, mineral
Groundnuts (Peanuts)
Group formula places atoms in groups corresponding to grouping in the actual molecule, e.g. aspirin, CH3CO.O.C6H4COOH.
Group tests for metallic radicals:
Group tests for cations, Tests for cations, prepare a solution:
Groups (in Periodic table): 1.5.0
Grout, calcium sulfate (cement between tiles)
Guaiacol, C6H4(OH)(OCH3), Methyoxyphenols:
Guanidine, CH5N3
Guanosine, C10H13N5O5, (guanine+ D-ribose)
Gulose, C6H12O6, aldose sugar, hexose, sold as: L-(+)-Gulose
Gum turpentine
Gummi bears (gummi fruit) with potassium chlorate:
Guncotton, Nitrocellulose, :
Gunpowder, black powder: potassium nitrate + sulfur + charcoal
Gunpowder, Potassium nitrate, KNO3
Gutta percha
Gutta solvent (93% higher boiling point hydrocarbons, 0.3% hexane, 0.2% petroleum fractions), Flammable
Guvacine, alkaloid
Gymnemic acid, C43H66O14, saponin
Gypenosides, saponins
Gypsum, CaSO4.2H2O,
Gypsum, calcium sulfate, plaster of Paris: 35.22.6
Gypsum, Tests for gypsum added to the soil: 6.15.5.

Gadolinium, Gd
, Gd (Johan Gadolin, 1760-1852, Finland), chips, foil, ingot, mesh, rare earth, identified 1880, from gadolinite.
Gadolinium is paramagnetic.
It is used in magnetic recording discs and tapes, in MRI contrast agents and green phosphors.
Gadolinium (III) chloride, anhydrous, powder, beads.

Gallium, Ga
, Ga (Latin Gallia France, Roman region including present day France and surrounding territory), blue-white metal, conchoidal
fracture, , in LEDs, in bauxite and zinc ores.
The discovery of gallium in 1875 by François Lecoq de Boisbaudran, France, was possibly the first element to predict the existence of
the periodic table.
He also discovered Samarium, Sm, and Dysprosium, Dy.
Gallium, brittle then melts at 298K, 29.77oC.
So "joke spoons" made of Gallium dissolve in a hot cup of tea!
Gallium arsenide, GaAs, semiconductor, in diodes, field effect transistors, integrated circuits, compact disc players because it transforms
electric current directly into laser light, for ultra-high radio frequencies, fast electronic switching, lasers (DH laser), in ink that contributes
to luminescence of euro bank notes
Gallium (III) acetylacetonate, C15H21GaO6
Gallium (III) bromide, Br3Ga
Gallium (II) chloride, Cl4Ga2
Gallium (III) fluoride, F3Ga
Gallium (III) iodide, GaI3
Gallium (III) nitrate hydrate, GaN3O9.xH2O
Gallium (III) oxide, Ga2O3
Gallium (III)-phthalocyanine chloride, C32H16ClGaN8
Gallium (III) sulfate hydrate, Ga2O12S3.xH2O
Gallium (III) sulfide, Ga2S3
Tetrabutylammonium tetrachlorogallate, C16H36Cl4GaN
Tris(dimethylamido)gallium (III), C12H36Ga2N6.

Gamboge, yellow dye, formerly for illustrations, poor lightfastness, poisonous, sap of Garcinia hanburyii, Clusiaceae.

Garum, liquamen, sauces made in ancient Greece and Roman empire from fermented fish intestines.

Gas, gases
See: Gas, (Commercial)
Gases, states of matter, solid (s), liquid (l), gas (g) aqueous solution (dissolved in water) (aq)
Gases: 3.30
Household gas, laboratory gas, "lab gas"
Gases by name, Ammonia to Xenon: 13.1.0
Air, atmosphere: 13.2.0
Bunsen burner gas: 22.6.3
Chemical vapours and smelling chemicals: 3.4.8
Density of gases (Table)
Fume cupboards, fume hoods: 2.4
Gas-pak: 2.11
Gas bags: 13.1.01
Gas burette, Dilute HCl with marble chips: 17.1.3
Gas constant, R, gas equation (PV = nRT): 20.0.7
Gas discharge tubes, Cathode ray tubes: 38.8.0
Gas expansion, Charles's law: 20.1.0
Gas generation apparatus: 3.32.0
Gas inhalation, vapour inhalation, EAR, CPR: 3.4.6
Gas installations and inspections: 2.1
Gas laws: 20.0
Gases by name, Ammonia to Xenon: 13.1.0
Gases dissolved in water: 3.25
Greenhouse gases
Hazards of gases: 3.8.0
Household gas, laboratory gas, "lab gas"
Molecular weight of gases (Table)
Packaging gases, propellants, food additives: 19.4.22
Prepare gases: 3.0.0
Relative molecular mass of gases: 13.1.02
Separate by heating, gases dissolved in water: 3.25
Standard temperature and pressure, STP, density of gases: 20.0.6
Saturation vapour pressure, SVP: 12.3.1
Saturation vapour pressure over water: 12.3.2 (Table)
Tests for gases and vapours: 1.0.0
Tests for gases collected in a respirometer: 6.6.12
Tests for gases from burning hydrocarbons:
Tests for gases, Lighted splint tests: Tests
Tests for gases with hot concentrated sulfuric acid:
Volume of gas dissolved in tap water:

Household gas, laboratory gas, "lab gas"
Butane gas, C4H10, compounds
Coal gas
Fossil fuels peak oil: 37.32.2
Laboratory gas, piped gas, "lab gas", Household gas
LPG gas, LP-gas, liquefied petroleum gas, compressed gas, bottled gas
Methane, natural gas, safety
Producer gas, air gas, similar to water gas, formed by passing air and steam over hot carbon.
Propane gas, C3H8
Town gas
Water gas, mixture of carbon monoxide and hydrogen gas, forms when steam passes over hot coke or carbon.

3.32 Prepare gases
Be careful! Prepare poisonous gases only in a fume hood or fume cupboard.
Prepare ammonia gas: 3.33.0
Prepare ammonia, Haber process: 3.33.01
Prepare butane:
Prepare carbon dioxide:
Prepare chlorine:
Prepare chloroform (trichloromethane): 16.1.14
Prepare ethane gas:
Prepare ethene (ethylene):
Prepare ethyne (acetylene):
Prepare gases by destructive distillation of coal: 10.6.5
Prepare gases from wood: 3.99
Prepare gases with a gas generation apparatus: 3.32.0
Prepare hydrogen gas:
Prepare hydrogen gas bubbles:
Prepare hydrogen with citric acid: 12.6.3
Prepare methane gas:
Prepare methyl chloride gas: 16.5.9
Prepare nitric oxide (nitrogen monoxide, NO): 3.44
Prepare nitrogen dioxide, [nitrogen (IV) oxide, NO2]: 3.47
Prepare nitrogen gas: 3.46
Prepare nitrous oxide (dinitrogen oxide, N2O): 3.45
Prepare oxygen with bleach: 3.49.3
Prepare oxygen with hydrogen peroxide: 3.49.0
Prepare oxygen with manganese dioxide and potassium chlorate - dangerous experiment
Prepare ozone: 3.50
Prepare sulfur dioxide by burning sulfur: 3.51.0
Prepare trichloromethane (chloroform): 16.1.14.

3.99 Prepare gases from wood
See diagram 3.2.99: Gases from wood
Put wood shavings or sawdust in a clamped Pyrex test-tube or hard glass test-tube
Connect the clamped test-tube to another test-tube standing in water and which has an outlet for the gas.
Heat the hard glass test-tube gently then strongly, until almost red-hot.
Ignite the wood gas coming from the jet.
The black residue is charcoal, carbon.

3.32.0 Prepare gases with a gas generation apparatus
| 12.3.2 Saturation vapour pressure over water (Table)
| See diagram 1.13a: Simple fume hood
| See diagram 3.32: Gas generation apparatus
| See diagram 3.33: Collect gas with an angle tube syringe
Be careful! Prepare poisonous gases only in a fume hood or fume cupboard, e.g. preparation of chlorine, hydrogen chloride, sulfur

1. See diagram 3.32: No. 1. Collect more dense gas by upward displacement of air (downward delivery), if molecular mass > 28.8.
The more dense gas sinks down into, and displaces, the less dense air upwards, e.g. preparation of carbon dioxide, nitrogen dioxide.

2. See diagram 3.32: No. 2. Collect less dense gas by downward displacement of air (upward delivery), if molecular mass < 28.8.
The less dense gas rises into, and displaces, the more dense air downwards, e.g. preparation of hydrogen, ammonia.
Use a borosilicate test-tube that is not cracked.
Clamp the test-tube to a stand.
Put the solid reagent in the sidearm test-tube and the liquid reagent in the reservoir.
Add the liquid reagent very slowly drop by drop.
Keep the reservoir tap closed and the reservoir full to prevent gases blowing back.
Grease the stopper and insert it so that if an accidental sudden increase in pressure occurs, the stopper blows out of the test-tube.
Use rubber tubing to collect the sidearm to a delivery tube that leads into the receiving test-tube.
Discard the first gas coming out of the delivery tube because it is mostly air.
Never allow a flame near the gas as it comes out of the delivery tube.
Some air probably remains in the receiving test-tube.
Use the gas bubbler to collect over water insoluble gases with similar density to air.
Some water vapour remains in the receiving test-tube.
Gases can also be collected in balloons, inflatable footballs, and plastic bags.

3. See diagram 3.32: No. 3. Collect insoluble gas, or not very soluble gas, of any density over water, i.e. by downward displacement
of water (water displacement), e.g. preparation of oxygen.
Fill one third of the water trough.
Fill a test-tube with water by placing it on its side in the water trough.
Put your thumb over the end of the test-tube and invert it.
Fix the end of the gas delivery tube inside or under the test-tube.
If the gas is slightly soluble in water its solubility will be less in warmer water, Some gases dissolve in water to produce heat and form
an acid solution, e.g. HCl, SO2, NO, NO2.
Some gases dissolve in water to form a basic solution, e.g. NH3.

4. See diagram 3.32: No. 4. Collect soluble gases in water (aqueous solution), e.g. Cl2..

5. See diagram 3.32: No. 5. When the gas preparation equipment uses downward displacement of water (Diagram 3.), or collection
in water (Diagram 4.),  water may be forced back into the equipment by atmospheric pressure, i.e. "sucked back", and break hot
glassware or dilute reactants.
To prevent sucking back use an inverted glass filter funnel.

6. See diagram 3.33: No. 6. Collect gas with an angle tube syringe that can collect and store gas of any density.

Gels gelatine, gelatin
Gels in the home kitchen:
Cooked collagen changes into gelatine: 3.0
Diffusion through a colloidal gel: 9.162
Gelatin, gelatine
Gellan gum:
Metallic salts gels, calcium carbonate gel, calcium acetate gel:
Nutrient gelatin: 9.2.29
Prepare gelatine gel:
Prepare glycerine jelly: 2.1
Make jelly with fresh pineapple and tinned pineapple:
Prepare silica gel:
Tests for pectin in jelly and jam:

Gelatin, gelatine
Gels, gelatine, gelatin, puragel, "Aeroplane jelly", Gels 12% Precast polyacrylamide
Gelatine, E441 (if contain SO2 may cause allergies)
Sold as: Gelatin Type A from Porcine Skin Gelatin Type B, (testing for proteins). 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.
Hydro gels, water absorbent polymers
Use jelly to style hair and grow seeds to see root structure.

, Ge (Latin Germinus germany), grey-white metalloid, crystalline, brittle, lustrous, metalloid, discovered by Clemens Winkler,
Germany, in 1886, produced from germanium silver ore argyrodite, germanite mineral, coal, and flue dusts.
Germanium and germanium oxide, GeO2, is used in semiconductors, (the first solid state amplifier, transistors), in alloys, infrared glass,
catalysts, e.g. for PET plastic, fluorescent lamp phosphors, infrared detectors, lenses.
Germanium (IV) chloride, GeCl4, germanium tetrachloride, Toxic by all routes, Highly corrosive, violent reaction with water
colourless, fuming liquid, acidic smell
Germanium ethoxide
Germanium Std (ICP / DCP).

See: Glassware, (Commercial)
Glass, silicon compounds: 7.2.3
Borosilicate glass, Pyrex: 7.9.10
Electrical conductivity of molten glass at high temperature:
Fibre glass
Glass cleaning with potassium dichromate solution
Glass cutting, tubing, cleaning: 2.0.0
Glass balls (all sizes), Glass beads (all sizes)
Glass knife (ceramic impregnated with diamond dust)
Glass transition temperature (Tg), chewing gum, cotton: 3.4.01
Glass wool: 3.3.6 (Safety)
Prepare coloured glass:
Test-tubes, glassware and microscope slides: 3.3.1 (Safety).

Fibre glass
Fibre glass resin, epoxy resins, uncured resins, may contain isocyanate residues, strong irritants to eye nose / respiratory organs.

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.".

Glucan (C6H10O5)n
Glucan (C6H10O5)n, D-glucose monomer polysaccharide, linked by glycosidic bonds.
Sold as:
1. Glucan from cell wall of baker's yeast (Saccharomyces cerevisiae)
2. β-D-Glucan from barley (1, 3)-β-D-glucan (BG), is a biomarker for candidiasis
3. β-1, 3-Glucan, Paramylon, from Euglena gracilis
Some α-glucans:
Dextran, H(C6H10O5)xOH
Glycogen, C24H42O21
Starch, α-1, 4- and α-1, 6-glucan, Some β- glucans
Cellulose, β-1, 4-glucan
Chrysolaminarin, β-1, 3-glucan, in phytoplankton
Laminarin, Laminaran, β-1, 3- and β-1, 6-glucan, in brown algae, Laminaria digitata, oarweed
Lichenin, β-1, 3- and β-1, 4-glucan, in lichen reindeer food
Pleuran, β-1, 3- and β-1, 6-glucan, from the oyster mushroom, Pleurotus ostreatus
16.7.11 Yeast, fermentation, brewing, beer
Zymosan, β-1, 3-glucan, found on yeast.

Gluconic acid
Carbohydrates, carbohydrate acids:
E574 Gluconic acid (anti-caking agent, sequestrant), Food additive
Glucose oxidase, Tests for glucose: 7.0
Oxidation of glucose, blue bottle experiment:
SCOBY, Symbiotic Colony Of Bacteria and Yeast: 9.3.1.

See: Glucose (Commercial)
Glucose, dextrose, C6H12O6, D-glucose, blood sugar, grape sugar, corn sugar
Dextrose Monohydrate
E575 Glucono δ-lactone (acidity regulator, raising agent)
E576 Sodium gluconate (Banned in some countries) (acidity regulator, sequestrant)
E578 Calcium gluconate (acidity regulator, firming agent)
E1102 Glucose oxidase (enzyme, acidity regulator)
Glucose, Monosaccharides:
Glucose 6-phosphate disodium salt D-, Glucose 6-phosphate barium salt D-,
Glucose 6-phosphate monosodium salt
Amylase (fermentation): 7.1.2
Glucose fermentation: 6.6.20
Glycaemic index (GI): 4.2.11
Heat different foods: 9.128
Heat glucose to form carbon: 12.7.1
Hydrolysis of starch by salivary amylase (ptyalin): 9.130
Lactic acid:
Lactase: 7.1.3
Left-handed and right-handed structural forms, D-sugars and L-sugars:
Non-enzymatic browning, caramelization:
Oxidation of glucose, blue bottle experiment:
Prepare glucose nutrient agar solution: 9.2.31
Prepare glucose nutrient agar: 9.2.16
Prepare glucose with starch: 12.7.15
Prepare glucose with sugar: 12.7.18
Prepare yoghurt, test milk quality: 4.3.17
Reducing sugars and non-reducing sugars:
Sorbitol E420, Sweeteners: 19.4.25
Split lactose from milk or whey using immobilized lactase: 4.2.11
Tests for glucose: Tests for glucose
Tests for reducing sugars, Benedict's test: 9.141
Test for starch with Fehling's solution: 9.142.3
Test for hydrolysis of starch, iodine test, Fehling's solution: 16.10.1
Tests, Multiple reagent strips:

Tests for glucose
Tests for glucose and fructose with Fehling's reagent: 9.142.4
Tests for glucose and starch, "Testape": 9.182 (See: 2.)
Tests for glucose and sucrose: 12.7.2
Tests for glucose, blood glucose, glucose tolerance: 4.0
Tests for glucose, Clinitest tablet: 1.0
Tests for glucose, Clinistix strip: 2.0
Tests for glucose concentration, ferricyanide test: 5.0
Tests for glucose, glucose oxidase test: 7.0
Tests for glucose, blood glucose, glucose tolerance test: 4.0
Tests for glucose, glycosylated haemoglobin test: 8.0
Tests for glucose in apples and sweets: 12.7.3
Tests for glucose, Nelson-Somogyi test: 6.0
Tests for glucose, urine test:
Tests for glucose, urine test, Diastix strip: 3.0.

Guanine, C5H5N5O
Guanine, (2-Amino-6-hydroxypurine), Guanin, (2-Aminohypoxanthine), purine base, constituent of nucleotides in nucleic acids.
(derived from purine, )unsaturated, planar bicyclic molecule, first found in sea birds excrete called guano used as fertilizer.
In DNA and RNA, stretches of guanine bases are reported to form stable four stranded helices.
Guanine, DNA and RNA:
4.4.0, (See 3.)
Guanine, Nucleic acid nitrogenous bases: 3.0.0

Glucose, C6H12O6
"D-(+)-Glucose", dextrose, glucose syrup, grape sugar, dextrose monohydrate, d-glucose, blood sugar, glucose
anhydrous, glucose (for babies), "Glucodin".
Glucose is called grape sugar because of its occurrence in grapes.
In table syrup, black treacle, ripe apples and cheap sweetening material for confectionery and sweets, e.g. barley sugar.
Glucose is only half as sweet as sucrose, sugar but is more easily digested.
It is manufactured by boiling starch with dilute sulfuric acid.
Glucose is a carbohydrate, the hydrogen and oxygen being in the same proportion as in water.
Common names: Corn syrup, "Karo" syrup.

Gluten, wheat starch and gluten (in wheat, barley, rye, gluten is gliadin + glutenin), gluten intolerance
Gluten proteins affect the baking quality of wheat by giving dough water absorption capacity, cohesivity, viscosity and elasticity.
Gluten proteins are divided into aqueous alcohol soluble gliadins and insoluble glutenins.
Gliadins are mainly monomeric proteins with molecular weights 28,000-55,000, and classified into alpha/beta-, gamma- and omega-types.
Disulphide bonds may be present as intrachain crosslinks.
Glutenins are aggregated proteins linked by interchain disulphide bonds, with molecular weights from 500,000 to > 10 million.
After reduction of disulphide bonds, the resulting glutenin subunits are solubile in aqueous alcohols as with gliadins.
Glutenin subunits are divided into the high-molecular-weight subunits (MW=67,000-88,000) and low-molecular-weight subunits (MW=32,000-35,000).
Gliadin causes elasticity and tenacity, or toughness, to the gluten, and the glutenin gives it strength.
Gliadin, L-glutamine, C29H41N7O9, molecular weight 631.687 g/mol, simple
protein, a prolamine, from the gluten of wheat, rye, and other cereals, the toxic factor associated with coeliac disease
Gluten powder, wheat starch, wheaten cornflour
Gluten intolerance: 19.2.5
Endospermic and non-endospermic seed: 9.109 (See: 2.2)
Prepare lactic acid with sourdough: 4.2.3 (See: Gluten)
Tests for carbohydrates, Molisch's test: 9.134 (See: 2.2)
Tests for starch with Fehling's solution: 9.142.3. (See: 4.)
Wheat starch and gluten:

Glyceraldehyde, C3H6O3. Sold as: DL-glyceraldehyde, D-(+)-glyceraldehyde
Aldose sugars:
Left-handed and right-handed structural forms, D-sugars and L-sugars:
Oxidation of glycerine: 12.7.6
Table Aldoses and ketoses
Test reducing sugars:

Glycerol, glycerin, glycerine, C3H8O3
Glycerol, glycerin, glycerine
Glycerol-phthalic anhydrides, thermoset: 3.8.8
Glycerol, trihydric alcohols, glycerol:
Glycerine jelly, adhesive, microscope slides: 2.1
Glycerine oxidation: 12.7.6
Glycerine with borax solution, colour change: 12.7.5
Glycerine with cobalt chloride solution: 12.7.8
Glycerine with sugar: 12.7.7
Glycerol-phthalic anhydrides, thermoset: 3.8.8
Glycerides, esters of glycerol:
Heat glycerine with sugar to form carbon: 12.7.7
Tests for glycerine: 12.7.4
Tests for glycerol: 12.12.3.

Glycerol, glycerin, glycerine, C3H8O3
Glycerine, glycerin, is a product containing at least 95% glycerol, C3H8O3, 1, 2, 3-propanetriol.
The terms glycerine, glycerin, glycerol may have no precise meaning in different countries and in different products.
Glycerol, glycerin, glycerine, C3H8O3, CH2OH-CHOH-CH2OH, 1, 2, 3-propantriol, propane-1, 2, 3-triol, trihydric alcohol, antifreeze
Glycerol, trihydroxypropane 1, 2, 3-propanetriol, glycyl alcohol, glycerol USP, oily so harmful if spilled on floor
Glycerol for lubricating rubber stoppers, mounting medium for temporary microscope slides
Glycerol, clear, viscous, colourless odourless syrupy fluid that readily absorbs moisture, propane-123-triol, 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, sweet taste and
no smell and has no action on litmus paper.
Glycerol is used in cosmetics, toothpaste, shampoo, loosens stains, medical uses, manufacture of explosives and shaving cream.
It is a by-product of the manufacture of soap.
Glycerol was discovered by K. W. Scheele, 1779, who heated olive oil with lithage.
Use glycerine smeared in ice cube trays to avoid trays sticking to freezer shelf.
Use glycerine added to the final wash rinse to stop woollen garments stretching.
Use glycerine to lubricate household mincing machines.
Use glycerine, rubbed in before washing, to remove lipstick stains.

Glycine, C2H5NO2, NH2CH2COOH, L-Glycine, aminoacetic acid (Gly), aminoethanoic acid, smallest and simplest amino acid
Glycine (Table of amino acids)
Glycine, DNA codons
Glycine and its sodium salt (flavour enhancer) E640
Glycine max, soya bean, soybean, vegetable, [soybean oil], Fabaceae: 19.2.11
Amino acids:
Separate amino acids by paper chromatography:

Glycogen, C24H42O21
Glycogen, α-1, 4- and α-1, 6-glucan
Glycogen, starches, amylum, glycogen:
Anatomy and physiology of meat: 19.3.2
Prepare Carnoy's solution: 4.8.

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 prepared from rabbit liver and from Mytilus edulis (Blue mussel).

Gold, Au
See: Gold Elements, Compounds, (Commercial)
Gold, table of Elements
Gold properties
Gold, Au, natural gold, for medical use: 35.20.18
Gold leaf electroscope: 4.145
Carat: 3.2.2
Ores and ore bodies: 35.3.0
Ormolu, looks like gold by coating brass with copper zinc tin alloy called gilt brass, gilded bronze using gold-mercury amalgam but
dangerous procedure, nowadays electroplated with gold, used for ormulu-decorated mantlepiece clocks, furniture, porcelain.
Touchstone, gold streak: 35.12.1.

Gold, Au (old English: golde), yellow, resists corrosion, transition series metal, malleable, ductile.
Gold beads, evaporation slug, foil, powder, nanopowder, rod, sponge, wire, microrods, nanorods, nanowires.
Gold, Au (aurum) is a yellow, lowest metal in the reactivity series so most unreactive transition metal, is found in nature as free element
form, available as gold leaf, occurs as the element and is used in coin alloys, electrical components, dentistry alloys, jewellery and as a
monetary standard.
Jewellery rings are not usually made from pure gold because they would screath easily.
White gold is usually gold alloyed with white metals, e.g. silver, palladium, manganese, nickel , which makes the gold ring whiter.
Yellow gold, the most popular alloy, is usually gold alloyed with zinc or copper, 18 K or 14K, for engagement or wedding rings, making it malleable and easier to work, but easily scratched or dented,
Gold alloyed with copper only, makes the gold ring redder, but with zink and copper makes the gold ring harder
No reaction with dilute HCl or H2SO4, air, water or concentrated oxidizing acids, e.g. HNO3 or H2SO4.
Reacts with aqua regia, "royal
water", that dissolves gold, the "king of metals" to form AuCl4.
Atomic number: 79, Relative atomic mass: 196.967, r.d. 19.3, m.p. = 1063oC, b.p. = 2970oC.
Specific heat capacity: 130 J kg-1 K-1.

Gold catalysts
(Acetonitrile), [(2-biphenyl)di-tert-butylphosphine]gold(I) hexafluoroantimonate, C22H30AuF6NPSb
Bis[chlorogold(I)], [1, 1-bis(diphenylphosphino)ferrocene], C34H28Au2Cl2FeP2
Chloro[(1, 1-biphenyl-2-yl)di-tert-butylphosphine]gold(I), C20H27AuClP
Chlorocarbonylgold(I), CAuClO
Chloro(dimethylphenylphosphine)gold, C8H11AuClP
Dichloro(DPPE)digold(I), C26H24Au2Cl2P2
Gold (III) bromide, AuBr3
Gold (I) chloride, AuCl
Gold (III) chloride, AuCl3
Gold (III) chloride trihydrate, HAuCl4.3H2O
Gold (I) iodide, AuI
Methyl(triphenylphosphine)gold(I), C19H18AuP
Sodium tetrachloroaurate(III) dihydrate, AuCl4Na.2H2O
Trichloro(pyridine)gold(III), C5H5AuCl3N
Tris(triphenylphosphinegold)oxonium tetrafluoroborate, C54H45P3OAu3BF4.

Attract water to a comb (See: Repeat): 4.41
Cellophane as a semipermeable membrane (See: 3.): 9.165
Density of different liquids (See: 1.0):
Golden syrup
Goldenrod indicator, electric writing: 5.6.11
Goldenrod oil (Solidago canadensis), Asteraceae.
Golden seal (Hydrastis canadensis), Ranunculaceae.
Goldenrod indicator paper, electric writing: 5.6.11
Hydrastine, C21H21NO6
Palmatine, C21H24NO4+
Prepare copper (I) oxide with golden syrup:

Greenhouse gases
Composition of the atmosphere and greenhouse gases: 37.42.1
Greenhouse effect in a model greenhouse, global warming, climate change: 37.43.0
Global warming and climate change: 37.43.1
Test for carbon dioxide as a greenhouse gas: 3.38.1.

Resins and gums: 3.0.0
Gum arabic, gum acacia, acacia, Irritant, Polysaccharide gums:
Gum guar, Gum locust bean, Gum tragathanth
Gum mastic, resin, used as chewing gum and Greek food flavouring, from Pistacia lenticus, Anacardiaceae
Gum rosin (mainly abietic acid, C20H30O2), colophony, Greek pitch, on violin bows and ballet shoes
Gummi bears (Gummi fruit) with potassium chlorate:
Prepare glues and pastes, adhesives, gums: 9.0.0.