Chemistry topics, Ci to Cy

School Science Lessons
2024-11-09

Chemistry, Ci to Cy
Contents
Carbonic acid, carbonated water, club soda, soda water
C.I., Pigment names, C.I. numbers
Cider, Prepare cider from apple juice
Cigarette, (Experiments)
Cinchonidine, alkaloid
Cinegalline, alkaloid
Cineole, eucalyptol
Cinnabar, HgS, (Geology)
Cinnamaldehyde
Cinnamic acid
Cinnamyl acetate
Cis-trans fatty acids, Hydrogenation
Citral
Citric acid
Citronellal
Citronellol
Citrine, Quartzite, (Geology)
Citrulline
Cocoa Project
Coconut Project
Columbianetin
Clathrate
Clay, (Geology)
Clayton yellow, acid-base indicator
Cryptopleurine, alkaloid
Clenbuterol
Climate change
Cling wrap, Vinyls, vinyl polymers, (Experiments)
Clinistix strip, Test for glucose
Clinitest tablet, (a form of Benedict's test for glucose)
Clivorine, alkaloid
Clock reactions, Rates of reaction, (Experiments)
Clot on boiling test, C.O.B, milk test, (Experiments)
Clothes on fire, (Safety)
Clothianidin, C6H8ClN5O2S, Neonicotinoid insecticide
Clothing, Protective clothing and equipment, (Safety)
Cloudy ammonia
Clove oil, eugenol
Club soda, Carbonic acid, soda water
Coade stone, (See:6.), Portland cement
Coal, coal gas, coal tar, (Experiments)
Coamidopropyl betaine, C19H38N2O3, surface-active agent, hair washing, may cause dermatitis
Cobalt, Co
Cocaine, alkaloid
Cochineal, Prepare carmine stain (Preparation)
Coconut oil, copra oil, edible oils, (Experiments)
Cod liver oil (vitamins A and D food supplement)
Codeine, alkaloid
Codonopsine, alkaloid
Coefficient of restitution, bounce, (Experiments)
Coffee,, coffee tins, Use, (Experiments)
Coffee, Approximate caffeine content of beverages, mg /cup
Cohesion, Hydrogen bonds
Coins, (Experiments)
Cola, (kola), (Experiments)
Colchicine, alkaloid
Collagen, (Experiments)
Colligative properties, Freezing point depression and boiling point elevation
Collodion, cellulose nitrate
Colloids and crystalloids
Colloids, diffusion
Colour, (Experiments)
Coltan, (Geology)
Combination reactions, (direct union of elements, Synthesis reactions) (Experiments)
Combustion, (Experiments)
Common ion effect
Common measures, Measure, (Measurement)
Competition for oxygen, Heat metals with oxides of another metal (Experiments)
Complex salt, Prepare cuprammonium sulfate
Composition of
Composting, humus
Compounds, (Experiments)
Compressed gas, LPG gas, LP-gas, liquefied petroleum gas, bottled gas, (Experiments)
Compresses, Prepare poultices, (Medicine)
Compressibility, Bulk modulus, modulus of incompressibility, K
Compressibility, Syringes for investigating air pressure, (Experiments)
Computers
Concanavaline A
Concentration, (ppm), (Chemistry)
Concentration, (List)
Concrete
Condensation polymers
Conductivity, Electrical conductivity, (Experiment)
Conductivity, (Soils)
Condy's crystals, KMnO4, (Experiments)
Conglomerate, (puddingstone), (Geology)
Congo red indicator solution, Prepare
Coniceine, alkaloid
Coniine, alkaloid
Conjugated dienes, diolefins (See: 3.)
Conjugated, Unsaturated fatty acids
Conjugated proteins, Glycoproteins
Conservation
Contact explosives
Constant boiling mixture, Azeotrope
Constantan, (constant resistance wire)
Construct molecular models
Consumable, low cost equipment
Contamination of groundwater
Continuous phase, Colloids
Convallatoxin
Convolvine, alkaloid
Cooking
Copernicium
"Copha", (Cooking)
Copolymers, Heteropolymers
Copper, Cu
Coprolites, fossilized animal dung
Coquelicot, red-orange poppy colour
COR, Hazard can destroy living tissue on contact, (Safety)
Cordite, Nitroglycerine
Cornin, Verbenalin
Coptisine, alkaloid
Coronadite, (Geology)
Correct names of chemicals, (Chemistry)
Corrosion, corrosive
Cortisone, C21H28O5, hormone
Corticosterone, C21H30O4, hormone
Cortisol, C21H30O5, hormone
Corundum, Al2O3 + (ruby, sapphire), (Geology)
Corynoline, alkaloid
Cotton, (Experiments)
Coulometer, Electrolysis of water, (Experiments)
Coumaric acid
Coumarin, C9H6O2
Coumarin glycosides
Coumarone, C8H6O
Covalent bonds
Covellite, CuS, (Geology)
CP, (Chemically Pure), chemicals standard
CPY3A4, liver enzyme
Cracking, catalytic cracking, thermal cracking
CRAF, biology fixative solution
Crassicauline A, alkaloid
Crayons
Cream, regular cream and sour cream
Cream of tartar, Potassium hydrogen tartrate
Cream of tartar, Prepare fruit salts, health salts
Creams and ointments, Prepare
Creolin, disinfectant
Creosote
Cresol red (IV), acid-base indicator
Cresols, O-cresol, C7H8O
Cresylic acid, cresols
Cresyl
Critical point / temperature
Crocidolite, Asbestos, (Geology)
Crocetin
Crocin
Crocoite, red lead ore, (See: Below Lead), (Geology)
Crown ether
Crucibles with lid
Crude oil, Fractional distillation of crude oil
Cryogenic solids and liquids, (Safety)
Cryolite, (Geology)
Cryptoxanthin
Cryptopleurine
Crystals, (Experiments)
CS gas
Curarine, alkaloid
Cubebene, sesquiterpenoid
Cubebin
Cucumber aldehyde
Cucurbitine, alkaloid
Cularidine, alkaloid
Cularimine, alkaloid
Cularine, alkaloid
Culture media to identify fungi, Prepare
Cumene, C9H12, methyl ethyl benzene
Cuminaldehyde, C10H12O, cuminal, monoterpene
Cup of tea, Prepare
Cupaloy, Copper-chromium alloys
Cupferron, Tests for iron
Cuprammonium sulfate, Prepare, (Experiment)
Cuprite, red oxides of copper, Cu2O, (Geology)
Curarine, alkaloid
Curcumin
Curcumene, sesquiterpenoid
Curie point, Curie temperature
Curium, Cm
Current electricity, electric current
Cuscohygrine, alkaloid
Cut grass smells, Geosmin, C12H22O
Cyanide, CN, compounds Cyan-
Cyanidin, Anthocyanin
Cyanidin galactoside
Cyanidin glucoside
Cyanidinrutinoside
Cyanamides, Melamine
Cyanin, Anthocyanin
Cyanocrylates, "Superglue"
Cycasin glucoside
Cyasterone
Cyclamates, cyclamic acid
Cyclic imines
Cyclitols
Cyclo-
Cyclodiene pesticides, aldrin, chlordane, dieldrin, endosulfan, endrin, heptachlor
Cycloastragenol
Cyclovirobuxine, alkaloid
Cycloartenol
Cymarine
Cymene, C10H14
Cynarine
Cysteine
Cystine
Cytidine, Nucleosides, (5.)
Cytisine, alkaloid
Cytochromes
Cytokinins, (Plant growth regulator)
Cytosine
Czapek Dox agar, Prepare, (to identify fungi) 6.5

Cinnamic acid
Cinnamic acid, C9H8O2, C6H5CHCHCOOH, 3-phenylpropenoic acid, monocarboxylic acid, toxic if ingested, white crystals, odour like honey, soluble in water
It may cause contact dermatitis, and may relieve smooth muscle spasms, It occurs in Myroxylon balsamum, Cinnamomum verum, (in inner bark for cinnamon sticks), Styrax benzoin, and Styrax balsam.
It occurs in Cinnamon bark oil, Coca Cola, Cinnamon leaf oil, Liquidambar styraciflua, Aloe vera, Alpinia calcarata Ethyl cinnamate, C11H12O2, cinnamic acid ethyl ester, an alkyl cinnamate, 4-methyl cinnamic acid, stain, dyestuff, Toxic if ingested
It is used in flavorings, perfume industry, to produce the sweetener aspartame, C14H18N2O5.
It occurs in Alpinia caerulea, Mandragora autumnalis, and Kaempferia galanga

Cinnamyl acetate
Cinnamyl acetate, C11H12O2, CH3CO2CH2CH=CH(C6H5), (from condensation of cinnamyl alcohol + acetic acid), is a fragrance ingredient, in chewing gum.
It occurs in Chinese cinnamon leaf oil, and Nicotiana species.
Ethoxyethanol C4H10O2
Ethyl ethanoate
Sodium acetate Ethyl ethanoate as a salt
Lead (II) acetate
5.7.9.1 Medroxyprogesterone acetate, Depo-Provera contraceptive
Copper (II) acetoarsenite Paris Green
3.7.36 Polyvinyl acetate
12.11.1 Tests for acetates

Constantan
Constantan, constant resistance wire, Eureka wire, CrAl (Kranthal) and NiCrm
(Nichrome: Nichrome wire
Constantan wire 15.6 ohm / m, 6.9 ohm / m, 0.98 ohm / m
Constantan is an alloy, about 40% nickel and 60% copper, having high volume resistivity and negligible temperature coefficient.
Resistance hardly changes with change in temperature.
It is used for resistance wire.
Also Eureka wire, CrAl (Kranthal) and NiCrm (Nichrome wire) have very high resistivity.
An optical pyrometer is used to measure very high temperatures from the colour of the radiant heat source.
Experiment
Attach a piece of copper and a piece of constantan to two wires.
Heat lead to above its boiling point of 327 o C.
Attach the wires to a galvanometer and insert the copper and constantan into the boiling lead.
The galvanometer can be calibrated to read temperature and act as a thermocouple to read the temperature of the molten lead.

Citric acid
Citric acid, C6H8O7 (anhydrous), HOC(CO2H)(CH2CO2H)2, CH2COOH-C(OH)COOH-CH2COOH
"Bomb Bags", citric acid + sodium bicarbonate --> carbon dioxide, (toy product)
Citric acid, tricarboxylic acid, colourless to white crystalline powder, orthorhombic crystals or granules, soluble in water, odourless, sharp taste, translucen
Citric acid, "2-hydroxy propane-1, 2, 3-tricarboxylic acid", MP about 100 o C, slightly deliquescent in moist air, loses water of crystallization in dry air,
Store in tight containers, very weak acid with little corrosive action
Acid compound in citrus fruits.
Sour taste of lemons, grapefruit, other citrus fruits, gooseberries and raspberries, caused by citric acid so it is an ingredient in artificial lemonade powder.
In health salts, citric acid acts with sodium bicarbonate in the mixture to produce the fizz when the mixture is added to water.
Citric acid is used for making up buffer solutions and forming citrate salts.
It is used as an acidulant to control pH and as an anticoagulant by chelating calcium in blood.
Also "2-hydroxy-1, 2, 3-propanetricarboxylic acid", is about 10% dry weight of lemons.
Low cost in supermarkets a pure form of citric acid is sold as "sour salt".
Lemon juice is used as a deodorizer, mild bleach, and cleaner.
Acids with baking soda: 12.1.18
Browning reactions of fruits and vegetables: 19.2.3.1
Citric acid cycle, Krebs cycle: 16.9.5
Citric acid solubility and temperature: 12.6.5
Citric acid with sodium hydrogen carbonate solution: 12.6.6
Heat citric acid to form carbon: 12.6.2
Lemons, lemon juice 5-8% citric acid
Prepare citric acid crystals with lemon juice: 12.6.1
Prepare hydrogen gas with citric acid: 13.3.15, (See: 2.)
13.3.15 Prepare hydrogen gas

16.9.5, Citric acid cycle, "Krebs cycle"
Krebs cycle is a cycle of reactions in mitochondria as part of aerobic cell respiration in which oxaloacetic acid is regenerated by a series of reactions in which ADP is converted to energy rich ATP, as part of the energy conversion processes in the body.
(Sir Hans Adolf Krebs, Germany / Great Britain, 1900-1981)

12.6.1, Prepare citric acid crystals with lemon juice
Squeeze a lemon with the help of a lemon squeezer and transfer the juice to a beaker.
Add an equal amount of water and boil the liquid gently over a gauze and tripod for quarter of an hour.
Filter the liquid while still hot into an evaporating basin.
The filtrate is a solution of citric acid.
Evaporate the solution on the gauze and tripod until only one third of it remains.
Then put it on one side to cool and crystallize.
The crystals of citric acid obtained in this way are not very pure.
They are usually coloured brown.
To obtain purer crystals, dissolve the impure substance in water and boil the solution with powdered charcoal (preferably "decolorizing" charcoal), for ten minutes.
Then filter the liquid and leave it in a hot place to evaporate and crystallize.

12.6.2, Heat citric acid to form carbon
Put 2 mL of citric acid crystals in a metal spoon.
Hold the end of the spoon in a paper holder and heat the citric acid crystals over a flame.
The first melt and then give off a vapour that ignites and burns with a yellow flame.
A black deposit of carbon remains on the spoon after the reaction, showing that citric acid is an organic substance.
The carbon can be burned off the spoon by continuing the heating.

12.6.5, Citric acid solubility and temperature.
The solubility of solid substances in water usually increases with rise of temperature.
However, calcium citrate is less soluble in hot water than in cold water.
Put 2 mL of calcium carbonate in a test-tube and add drops of citric acid.
Carbon dioxide forms.
When the reaction stops, add more drops of the acid solution until the calcium carbonate has completely dissolved.
The clear liquid is a solution of calcium citrate.
Hold the test-tube in a paper holder and heat the solution over a flame.
A white precipitate of calcium citrate forms in the liquid, because of the lower solubility of calcium citrate at higher temperatures.

12.6.6, Citric acid with sodium hydrogen carbonate solution
C6H8O7 + 3NaHCO3 --> C6H5Na3O7 + 3CO2 + 3H2O
citric acid + sodium hydrogen carbonate --> sodium citrate + carbon dioxide + water
Lemon juice with sodium bicarbonate
Do not use a glass container.
Put lemon juice into a plastic or tin plate container that can be sealed with a lid, e.g. coffee powder tin, film canister.
Squash absorbent paper, e.g. toilet tissue, newspaper, into the container so that it is wedged against the sides of the container, but does not touch the lemon juice.
Sprinkle sodium bicarbonate powder over the paper.
Seal the container then invert it.
The citric acid in the lemon juice reacts with the sodium hydrogen carbonate to form carbon dioxide, which increases the gas pressure in the container and blows off the lid.
Such reactions have been used to make simple rockets.
If the container is attached to a rocket stick, by Newton's third law the force with which the lid is blown off (down), is equal to an equivalent upward force up, so the rocket moves up.
Be careful! Do the experiment outside with a small amount of reactants.
Stand well away from the container after inverting it and do not look down from directly over the container.

Citrulline
Citrulline, C6H13N3O3, L-citrulline, delta-Ureidonorvaline, amino acid, nitric oxide synthase inhibitor, protective agent, micronutrient, irritant
It occurs in watermelon Citrullus, in sesame Sesaman indicum.

Cigarette
Butane gas: , (in cigarette lighters)
Cellulose triacetate: 3.5.8, (in cigarette filters)
Cerium: , Ce, with Lanthanum, in cigarette lighter ignition flints
Microbial decomposition of thin paper, cigarette paper: 4.2.8, (See 2.)
Nicotine, C10H14N2
Nicotine spray: 4.7.3, (Agriculture)
Tests for cigarette smoke: 16.5.6

Cinnamaldehyde,
Cinnamaldehyde, C9H8O, trans-cinnamaldehyde, cinnamaldehyde flavonoid. yellowish oily liquid, cinnamon odour, sweet taste, cinnamon flavour and odour.
It is a skin irritant, toxic in large doses, excreted in urine as cinnamic acid.
Cinnamaldehyde is not soluble in water, main component in cassia oil, cinnamon bark oil, flavouring compounds for cinnamon flavour.
Cinnamon bark has cinnamon and cassia aroma.
Cinnamaldehyde can be made synthetically, but is more commonly obtained from the steam distillation of the oil of cinnamon bark.
Cinnamaldehyde is hypoglycemic, vasodilator, antifungal, sensitiser, insecticide, scent repels cats and dogs.
It is used as a corrosion inhibitor for steel and other ferrous alloys in corrosive fluids.

Clathrate
Clathrate, includes "guest molecule" in host molecule's lattice cage, e.g. Dianin's compound, 4-p-hydroxyphenyl-2, 2, 4-trimethylchroman

Collagen
Anatomy and physiology of meat:: 19.2.1, (See: 2.)
Aniline blue:: 7.7, (stains collagen), Prepare
Cooked collagen changes into gelatine: 19.2.8.5
Fibrous proteins and globular proteins: 16.6.0 (See: 1.)
Gels:: 7.8.5, (See 2.), (collagen is denatured)
Observe roasting meat:: 19.2.8.1, (slow cooking)
Prepare gelatine gel: 7.8.8
Collagen
Collagen is an insoluble fibrous protein in connective tissue, e.g. tendons, skin, bone.
Collagen is about one third of the protein in mammals is collagen.
Collagen is used sutures, leather substitutes, and food casings.
Vitamin, C is a water-soluble vitamin essential for the formation of collagen in connective tissue

Columbianetin,
Columbianetin, C14H14O4, dihydro-oroselol, zosimol, a furanocoumarin. a tertiary alcohol, irritant
It occurs in celery stalks (Apium graveolens), (Xanthoxylum arnottianum), and (Heracleum sprengelianum).

Curium, Cm
Curium, Cm, radioactive metallic actinide
Curium, Table of the Elements
Curium is named after Marie Curie, 1867-1934, Poland / France.(br)

Clove oil
Clove oil, eugenol: 16.3.6.9
Clove, (Syzygium aromaticum), Myrtaceae
Eugenol, C10H12O2, (in oil of cloves, cinnamon leaf oil, West Indian Bay oil)
Clove oil, oil of cloves, is used for microscopy.
Use cloves in shelf corners to get rid of ants.
Use oil of cloves solutions for removing fungus infections from households.

Coal
Coal, coal tar, solid, lumps, peat, lignite (brown coal) bituminous coals, anthracite, coke
Coal: 35.3.2, (Geology)
Coal tar products:: 16.4.0, creosote
Coal gas
Coal tar products, creosote: 16.2.10
Coal seam gas, CSG, and coal to liquid, CTL, projects: 37.1.2
E102, Tartrazine (coal tar dye)
Fuchsine, fuchsin (magenta)
Jet black, jet, is a type of hard coal, which can be polished to make "jet black" beads to be used for mourning attire.
Jet from fossilized monkey puzzle trees has similar triboelectric properties to amber, generate static charge, so it may be called "black amber".
Prepare gases from coal: 16.1.2
Prepare ammonia, Haber process: 3.01, coal tar
12.6.0.2 "Sulfur" in coal, iron (II) sulfide (pyrite).

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, used for a "safety smell"
Lately, "synthetic natural gas", SNG, is synthesized from coal or petroleum

Cobalt, Co
See: Cobalt, Table of Elements
See: Cobalt and compounds Australian Government
Cobalt
Cobalt, Co (German Kobalt demon, which interfered with silver mining!)
Cobalt ion Co 2+ , Cobalt (II) AAS Solution, pellets, powder.
Cobalt (German kobold, goblin of the mines), was associated by miners with arsenic and sulfur health-damaging impurities.
Cobalt salts colour glass blue, plant and animal nutrition, trace element, transition hard, grey metal.
Cobalt forms complex ions, e.g. CoH2O)6] 2+ , magnetic below 1075 o C, essential element, but toxic in excess.
It is used in alloys radiography, magnets, steel.
Cobalt (II) oxide used to colour glass blue.
Occurs in the body only as Vitamin B12, (cyanocobalamin), (C63H88CoN14O14P), produced by the bacterium Escherichia coli
Cobalt (German kobold, goblin of the mines), was associated by miners with arsenic and sulfur health-damaging impurities.
Atomic number 27, Relative atomic mass 58.9332, RD 8.90, MP = 1492 o C, BP = 2900 o C.
Specific heat capacity 435 J kg -1 K -1
Atomic number 27, Relative atomic mass 58.9332, RD 8.90, MP = 1 492 o C, BP = 2 900 o C
Specific heat capacity 435 J kg -1 K -1
Cobalt has 28 radioisotopes, including:
Cobalt-60, (60Co), is used for sterilizing and for treating cancer patients.
Cobalt-57, (57Co), is used in medical and scientific research.
Toxic salts: Cobaltous aluminate (cobalt blue), Cobalt magnesium borate (cobalt violet, violet 48), Cobaltous oxide (cobalt green)
Tests for cobalt: 12.11.3.18

12.6.9, Properties of cobalt salts
Co(H2O)6 2+ = pink hexa aqua cobalt (II) ion, hexaaquacobalt (II) ion
1. Heat cobalt carbonate in a small hard glass tube.
The brown residue is cobalt (II) oxide.
CoCO3 --> CoO + CO2
Transfer the oxide to a crucible and heat to redness.
The black residue is cobalt (II) cobalt (III) oxide, Co2O4.
2. Add excess of hot sodium hydroxide solution to 3 cm of a cobalt salt solution.
Note the pink precipitate of cobalt (II) hydroxide.
Note the change to brown cobalt (III) oxide, Co2O3 on exposure to air.
Cobalt (II) hydroxide is soluble in ammonia solution, NH3 (aq) ("ammonium hydroxide"), because of the formation of the complex ion Co(NH)6 2+ .
Co 2+ + 2OH - --> Co(OH)2 (s)
3. Add a suspension of bleaching powder to a test-tube containing a cobalt (II) salt solution.
Note the black precipitate of cobalt (II) hydroxide.
The bleaching powder acts as an alkaline hydroxide and an oxidizer.
Divide the precipitate into two parts.
Add excess hydrochloric acid to one part to obtain a brown solution of the unstable cobalt (II) chloride.
Heat the second part to obtain oxygen gas and a residue containing cobalt (II) oxide.
Cobalt (II) hydroxide behaves as a weak base.
4. Evaporate cobalt (II) chloride solution to dryness and note the blue colour of the anhydrous salt.
Cobalt chloride is stable compare to hydrated iron (II) chloride.
Write on a piece of paper with dilute cobalt chloride solution.
Leave to dry and the writing becomes invisible.
Heat the paper from below and writing appears bright blue, because of dehydration of the salt.
So cobalt chlorine solution is a kind of "invisible ink".
5. Put drops of pink cobalt chloride solution on filter paper, hold it over a flame, see brilliant blue colour of the anhydrous salt.
A weather indicator can be made by soaking white paper in a concentrated solution of cobalt chloride.
6. Cobalt ions with carbonate ions.
Pink cobalt ions solution, Co(H2O)6 2+ , reacts with carbonate ions solution to form gelatinous calcium carbonate precipitate in a pink solution.
Co 2+ (aq) + CO 3 2- (aq) --> CoCO3 (s)
7. Add a dilute solution of ammonia to a cobalt chloride solution to form a green-blue precipitate.
Add excess ammonia to dissolve the precipitate to leave a light brown solution.
Leave to stand to allow oxidation in the air to form a deep red-brown solution.
The same colour change occurs if hydrogen peroxide is used.
Co(H2O)6 2+ + 2NH3 --> Co(H2O)4(OH)2 + 2NH4 +
(Hydrogen ions are detached from the complex ions to form a green-blue neutral complex precipitate).
Co(H2O)6 2+ + 2NH3 --> Co(NH3)6 2+ + 6H2O
(With excess ammonia, the neutral complex dissolves to form a green solution containing hexa amine cobalt (II) ions, hexaaminecobalt (II) ions).
Co(NH3)6 2+ + O2 in the air --> Co(NH3)6 3+
(Leave to stand so that the hexaminecobalt (II) complex is oxidized to deep red-brown hexaminecobalt (III) complex).
2Co(NH3)6 2+ + H2O2 --> 2Co(NH3)6 3+ + 2OH -
(It is the same colour change as above reaction only faster).
8. Add limewater CaOH)2, or sodium hydroxide solution to cobalt chloride solution.
A light blue precipitate forms that on standing the solution turns pink.
Co(H2O)6 2+ + limewater --> Co(H2O)4(OH)2 (neutral complex)
9. Test for aluminium compounds
Put drops of red cobalt chloride solution on filter paper.
Add drops of aluminium sulfate solution.
Dry the filter paper over a flame then ignite it over a ceramic bowl.
The blue ash formed is a test for all aluminium compounds in solution.
10. Tests for heat, heat-sensitive paper
Add cobalt (II) chloride solution to ammonium chloride solution (sal ammoniac).
Dilute this solution until it is pale pink.
Soak absorbent paper in the solution and leave to dry and become almost colourless.
The paper turns bright green colour when heated.

Cobalt compounds
Cobalt (II) carbonate, CoCO3.xH2O
Cobalt (II) chloride
Cobalt (II) Cobalt (II) oxide, CoO
Cobalt compounds
Cobalt deficiency in soils:: 6.13.3
Cobalt toxicity:: 4.6.6
Concentration and temperature, cobalt (II) chloride-6-water;: 17.1.9.6
Hydrogen peroxide with potassium sodium tartrate, cobalt (II) chloride catalyst: 17.7.18
Properties of cobalt salts:: 12.6.9
Properties of cobalt salts: 7.2.2.14
Sodium hypochlorite decomposition, cobalt sulfate catalyst: 17.3.9.1
Tests for cobalt:: 12.11.3.18
Tests for cobalt (nitroso-beta-naphthol test): 12.11.3.18
Tests for water with cobalt (II) chloride paper:: 8.2.2
Tests for heat, heat-sensitive paper: 5.3.10

Cobalt (II) carbonate, CoCO3
Cobalt (II) carbonate hydrate, CoCO3.xH2O
Cobalt (II) carbonate (basic) (blue glaze for craft, for spectral analysis with flame test for cobalt), Harmful
Cobalt (II) carbonate, Low cost from pottery supplies stores
Cobalt (II) carbonate with hydrochloric acid forms cobalt (II) chloride
Cobalt (II) carbonate with with nitric acid forms cobalt (II) nitrate

Cobalt (II) chloride,
Cobalt chloride, CoCl2, cobalt (II) chloride, CoCl2.6H2O cobalt (II) chloride hydrated, cobalt (II) chloride-6-water, harmful if ingested, environment danger
Cobalt (II) chloride decahydrate, cobalt (II) chloride-6-water: 17.5.1
Cobalt (II) chloride-6-water, For 0.1 M solution, 23.8 g in 1 L water
Cobalt (II) chloride solution, crystals CoCl2.6H2O, invisible writing ink 3.2.5.2
Tests for heat, heat-sensitive paper: 5.3.10
Cobaltous chloride AAS Solution
Glycerine with cobalt chloride solution: 12.1.8
Tests for water with cobalt (II) chloride paper: 8.2.2

Cobalt (II) nitrate hexahydrate, Co(NO3)2.6H2O, cobalt (II) nitrate hydrated
Harmful if ingested, red-brown, deliquescent, monoclinic crystals, soluble in water and other solvents
Cobalt nitrate, For 0.1 M solution, 29 g in 1 L water

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

12.11.3.18 Tests for cobalt
Organic reagent: Nitroso-beta-naphthol, 1-nitroso-2-naphthol, C10H7NO2, 1 g in 50 mL acetic acid
Dilute to 100 mL Add reagent to neutral or slightly acid solution.
A brown colour indicates the presence of cobalt.
Use in Group IV when in solution after treatment with KClO3 and acid, or use the solution after Group III.
Cu, Fe, Sn, Ag, Cr, Bi, all interfere with the test.

Cocaine
Cocaine, , C17H21ON4, benzoylmethylecgonine, alkaloid ester, benzoic acid ester, local aneasthetic, vasoconstrictor, powerful CNS effects like amphetamines
It is a drug of abuse, causes inhibition of dopamine uptake, high doses mood elevating effects and toxic reactions, in Erythroxylum coca (coca plant)
Cobalt (II) thiocyanate, Co(SCN)2, Harmful, Environment danger, in Scott's reagent test for cocaine
Copolymer, Polymer from linking different monomer types, e.g. cocaine, curare, caffeine, piperine
See diagram: Cocaine
See diagram, 16.20.0 Caffeine, cocaine, coniine, heroin, LSD
See diagram 16.21.7, Mescaline, dopamine, psilocybin, serotonin, ergine, LSD, tropane
Tropane Alkaloids:: 16.6.16
Cocaine and amphetamines:: 5.7.3
Cocaine and crack cocaine, Abuse:: 5.5.10
Coca, Erythroxylon coca, Erythroxylaceae
Hallucinogenic drugs, hallucinogens: 5.5.15

Coins
Coins, Biology
Platelets are irregular in shape and are usually seen in small groups like piles of coins
Presence of bactericidal substances using a coin and Bacillus mycoides: 4.1.12
Coins, Chemistry
Coinage metals
Copper coins, alloy of zinc and tin in copper
Copper, former English penny coin was made of copper, but was discontinued in 1971.
Corrosion of alloys, restore bronze coins: 15.1.5
Cupronickel alloys of Cu and Ni, "silver" coins, Local Purchase
Gold coins, e.g. the Australian $1 coin is an alloy of aluminium and nickel in copper.
Oxidize copper coins: 12.7.9.1
Prepare verdigris with copper and vinegar: 12.11.1
Coins, Physics
14.3.0 Coins
Electricity from two coins: 33.4.51
Conduction of heat by a coin on paper: 23.7.13

Cola, kola
"Cola-Mentos Fountain Kit" (toy product)
Cola acuminata, cola tree, Goora nut, (Abata cola), Sterculiaceae
Cola gigantea, giant cola, Sterculiaceae
Cola nitida (C. acuminata), Kola nut, Cola nut, [theobromine, caffeine alkaloid], Sterculiaceae
Cola vera, kola nuts, herbal medicine, Sterculiaceae
The recipe for the beverage Coca-Cola is said to be a commercial secret.
The Coca-Cola product Coke Zero, now rebranded Coca-Cola Zero Sugar, contains the artificial sweeteners aspartame and acesulfame potassium (Ace-K).
Caramel is used as a flavouring and food colouring E150 in candy and Coca Cola
Cinnamon bark oil (contains cinnamaldehyde, eugenol, benzyl benzaldehyde, pinene), occurs in Coca Cola
Contraception, Cola put into the vagina after having sex does not work as a contraceptive.
Methyl imidazole, 4-methylimidazole, 4-MEI, is a caramel colouring in cola drinks.
Cola drinks contain phosphoric acid.
Beverage can pressure: 12.2.4
Cola: 19.6.0
Soft drinks, carbonated beverages, fizzy drinks, sports drinks
Carbon dioxide: , (Experiments)
Carbon dioxide has mass: 12.1.13
Carbonic acid: 3.9.0
Density of cola and diet cola: 11.2.5
Beverage can, drink can:
Caffeine, Experiments: 9.2.0
Freezing point depression of carbonated water, cola: 24.1.05

Colour
18.7.9 Tests for colour of water, (Experiments)
35.1.4 Color of rocks and minerals, (Geology)
18.2.0 Colorimetric tests, Total dissolved solids and suspended solids in water, (Experiments)
11.3.3 Colour change of diluted potassium permanganate
12.2.4.02 Coloured precipitates, double decomposition reactions, (Experiments)
19.1.7 Colours, food colours, food additives

Combustion
Combustion: 8.2.0
Combustible solids: 3.5.6
Combustion of butane: 16.6.4.0
Combustion of gasoline, Distil crude oil and collect the fractions: 10.3.9
Burning sugar cube, combustible cube: 17.3.12
Fire safety and fire equipment: 3.5.0
Heat sources, candles, heat substances, thermal decomposition: 8.3.0

Composition of
Composition of edible oils: 3.9.3
Composition of the atmosphere and greenhouse gases: 37.2.2
Prepare sea water crystals, composition of sea water: 3.1.14

Compounds
A chemical compound contains two or more atoms of different elements that share a chemical bond.
Direct union of elements to form compounds: 8.0.0
Synthesis reactions (combination reactions, direct union of elements): 12.2.2.0
Decomposition reactions: 12.2.2
Pure substances and impure substances, elements and compounds: 7.2.0

Contact explosives
Acetone peroxide, TATP (triacetone triperoxide), C9H18O6, high explosive, white powder, bleach smell
Lead azide, Pb(N3)2, contact explosive, in detonators
Mercury (II) fulminate, Hg(CNO)2.H2O, Hg(ONC)2, initiator in detonator and percussion
Nitrogen triiodide, NI 3: 12.19.6.13
Nitroglycerine: 16.6.10
Picric acid
Potassium chlorate in pyrotechnic flash powders: 15.2.13.2
Silver fulminate, AgCNO, contact explosion, extremely sensitive, tiny amounts in children's noise-making toys
Silver nitride, Ag 3 N, contact explosive unstable, occasionally unwelcome occurrence in silver experiments
Tetrasulfur tetanitride, S4N4
TNT, trinitrotoluene, CH3C6H2(NO2)3

Conservation
Conservation of mass: 11.3.0
Conservation of energy, work, energy, kinetic energy and potential energy: 9.2.0
Soil conservation: 6.5.0,

Copernicium, Cn
Copernicium, Table of the Elements
Copernicium, RSC
Copernicium named by IUPAC in 2010 after Nicolaus Copernicus (1473 -1543), Prussia, now Poland

Corrosion
Corrosion,: 15.1.0, (Experiments)
Corrosive substances: 3.4.4, (Chemical safety)
Corrosive sublimate, Mercury (II) chloride
Corrosive to metals: 4.16

Cotton
Cotton bush, (Gossypium barbadense)
Card and cotton reel spool, lifting plate: 13.2.4, (Physics)
, Cotton, burning test for natural fabrics: 4.2.4
Glass transition temperature (Tg), chewing gum, cotton: 3.4.03
Flaming and cotton wool plugs: 4.4.3, (Microbiology)
Fluorescent whitening agents in washing powders: 12.12.03.3a
Tests for cellulose, iodine tests for cellulose: 9.3.8
Cotton
Cotton buds, double -ended, pack / 100
Cotton cord, 2.5 mm
Cotton Blue (aniline blue, methyl blue, Helvetia blue, acid blue 93), C.I. 42780, C37H27N3Na2O9S3, histology and fungus stain
Cotton Red (Gossipmine, CI 50240) CI22120, CI Direct Red 28, Congo Red
Cotton reels, pack 144
Cotton seed oil, cottonseed oil (Gossypium), meal for chickens
Cotton wool, pack 450 g, Cotton wool is almost pure cellulose
Cotton wool balls, Dove Swisspers, 25 g, pack / 60
Cotton wool squares, Dove Swisspers, box / 80
Calico

Cracking
Thermal cracking is the use of heat and pressure for controlled breakdown of naphtha, C 10, to form smaller hydrocarbon molecules and light olefins (alkenes)
For example ethylene, propylene butylene, which can later be polymerized.
The process increases the yield of petrol (gasoline), C 6-10, from crude oil and increases the octane rating.
Catalytic cracking
Catalytic cracking is the use of silica or aluminium as a catalyst to lower the temperature needed to break down heavy hydrocarbons in crude petroleum, or liquefied petroleum gas and natural gas to form monomers, e.g. ethane, propane.
The smaller molecules formed by cracking often have branch chains.

Coumaric acid, C9H8O3
Coumaric acid, p-Coumaric acid, 4-Hydrocinnamic acid, yellow-green crystalline powder, in flavours and pharmaceuticals

Crystals
"Crystal" may refer to soda-lime glass containing lead monoxide, often called "lead crystal" and use in wine glasses and ornaments
Breaking strains, brittleness: 34.5.2.0
Cleavage, fracture, twin crystals, crystal faces: 35.9, (Geology)
Colloids and crystalloids: 7.8.0
Condy's crystals: , KMnO4
Crystal faults, crushing salt: 34.8.6
Crystal growth in a film: 34.8.5
Crystal systems, crystal habit, crystal form: 35.8, (Geology)
Crystals of different salts, storm glass: 12.10.1.0
Elasticity (Tension, Compression, Shear): 34.5.01
Fractional crystallization of sea water: 7.7.14
Ice model: 34.8.2
Ice nuclei: 34.8.4
Materials from the Earth: 34.3.0
Mechanical properties of materials, elastic, ductile, malleable: 34.5.0
Phenyl salicylate, C13H10O3
Poisson's ratio, v: 34.5.06
Prepare crystal violet, microscopy stain: 7.21
Prepare crystal violet solution: 22.01
Prepare crystals: 3.0.0
Prepare crystals , Water of crystallization, (List)
Rocks and minerals, definitions, mineral classification and origin: 35.4
Separate by recrystallization: 10.9.0
Shape memory alloy, Nitinol: 34.8.7
Shape or form (crystals): 35.19
Solid models, sphere packing: 34.8.8
Transparency (transparent, translucent, opaque, refraction): 35.7
Water of crystallization: 3.6.0

Cubebin
Cubebin, , C20H20O6, tetrahydro-3,4-dipiperonylfuran-2-ol, lignan, benzodioxole, secondary alcohol, lactol, analgesic, anti-inflammatory, antimicrobial
It is extracted from leaves of Piper nigrum

Cyanide, CN
A cyanide contains the cyano group C≡N.
An inorganic cyanide is a salt or ester of hydrocyanic acid, containing the group -CN or the Cyanide anion −C≡N.
Cyanide, CN,: See diagram, 16.2.4.2.2 Cyanides
Cyanide, CN, cyanides CN - , nitriles, cyanide reagent test kit
Cyanide (cyano), CN-, monodentate ligand
Cyano -CN
A nitrile is an organic compound in which an alkyl group is directly attached to the carbon of a cyanide group.
Nitrile: 16.7.6
Hydrocyanic acid, hydrogen cyanide, Extremely Toxic: 16.2.4.2
Amygdalin, C20H27NO11, cyanogenic glucoside
Cyanide compounds, Cyan-
Cyanamide
Cyanic acid, C3H3N3O3 fulminic acid (salts fulminates)
Cyanidin, C15H11O6
Cyanine dyes
Cyanoacetic acid, C3H3NO2
Cyanocrylates, (CH2)C(CN)COOR, "Superglue": 16.2.4.7
Cyanogen, (CN)2
Cyanuric acid

Cyanamide, CH2N2
Cyanamide, CH2N2, NH2CN, carbimide, cyamamide, colourless, deliquescent crystal, soluble in water, alcohol and organic solvents, fertilizer, defoliant
Cyanamides, inorganic salts, CN2 2- : 16.2.4.2.1
Calcium cyanamide, CaCN2, often called "cyamamide" or "nitrolime", fertilizer

Cyanidin, Anthocyanin, C15H11O6 +
Cyanidin, Cyanidol chloride, Pentahydroxyflavylium, anthocyanidin cation, an anthocyinidin, neuroprotective agent, antioxidant, red-purple pigment in berries, apple, plum, red cabbage, red onion
Cyanidin 3-O-glucoside, 3G, kuromanin, C21H21O11+
Cyanidin-3-rutinoside, C27H31ClO15, decrease blood sugar levels
Hydroxycyanidin, in Alstroemeria species
Cyanide, CN,: See diagram, 16.2.4.2.2 Cyanidin
Cyanidin glucoside, C21H21O11+
Cyanidin glucoside, Cyanidin 3-O-glucoside, Cyanidin galactoside, Kuromanin, anthocyanin cation, a beta-D-glucoside
It occurs in american cranberry (Viburnum trilobum), cherries, olives, and in grapes.

Cyanidinrutinoside, C27H31O15+
Cyanidinrutinoside, Cyanidin 3-O-rutinoside, Cyaninoside, Sambucin, rutinoside, anthocyanin cation, disaccharide derivative, a benzene
It occurs in asparagus, and in blackcurrant.

Cyanin, C27H31O16 +
Cyanin, Cyanidin 3, 5-O-diglucoside, a beta-D-glucoside, anthocyanin cation, red plant pigment
It occurs in Sambucus species, elders.

Cyanine dyes
Cyanine dyes, R2N-(CH=CH)n-CH=N + R2, fluorophore labels for proteins and nucleic acids
Cyanine acid blue R dye

Cyanoacetic acid
Cyanoacetic acid, , C3H3NO2, yellow-brown liquid, unpleasant odour, mixes with water.

Cyanocobalamine
Cyanocobalamine, C63H88CoN14O14P, Vitamin B12, water-soluble vitamin, necessary for haematopoiesis (blood cells and plasma production)
Deficiency causes anemias.

Cyanogen
Cyanogen, (CN)2, (i.e. two joined "CN"s), NC≡CN, (note triple bond), colourless, nasty smell, Toxic

Cyanuric acid
Cyanuric acid, C3H3N3O3, (CNOH)3, conditioner, stabilizer, 18.7.14
Cyanuric acid CNOH)3, H3C3N3O3, is used in for swimming pools, purifying tablets, white soluble crystals, solution converts to urea.
Cyanamides: 16.2.4.2.1
Cyanuric acid, conditioner, stabilizer: 18.1.6, conditioner, stabilizer, (Swimming pools)

Cyanuric chloride
Cyanuric chloride, C3Cl3N3, colourless crystalline, strong pungent odour, slightly soluble, toxic by ingestion and inhalation

Cyasterone
Cyasterone, C29H44O8, phytosterol, a steroid lactone, a hydroxy steroid, a phytoecdysteroid, insect moulting hormone activity, inhibits insect ovary development
It occurs in Ajuga species

Cycasin
Cycasin, , C8H16N2O7, a carcinogenic and neurotoxic glycoside
. It occurs in the seeds of all cycas genera, e.g. (Cycas revoluta) and (Zamia pumila), causes the fatal nervous disease "Zamia staggers" in herbivores.
Indigenous Chemistry
Detoxification of cycasin
The development of complex detoxification processes by the rainforest Aboriginal peoples of North Queensland was driven by the food needs of that society.
Data, gathered from experiments that attempted to remove toxins, allowed this cultural group to modify and perfect the detoxification processes.
Europeans survived a near-fatal experience after consuming under-processed cycad kernels on the first voyage to Australia by Cook and his party in 1770.
Many of the detoxification processes of poisonous plant foods employed by Aboriginal peoples throughout Australia have been documented.
These detoxification processes provide evidence of Australia's First Nations peoples’ extensive scientific knowledge of chemical and physical processes.
Cycads are a source of carbohydrates, but they contain toxic cycasin, which causes vomiting, nausea and abdominal pains, damage to the nervous system and liver.
Cycasin has been linked to various types of cancer.
Cycasin consists of glucose chemically bound to the active toxic substance, methylazoxymethanol (MMA), C2H6N2O2.
In water, cycasin is broken up into these two parts, thus facilitating the removal of the toxic and water soluble MMA - Methoxymethanol.
This is a slow reaction, so Aboriginal peoples had to discover measures to speed up the reaction, increasing the contact surface with water and the temperature.
If the untreated cycad kernels are consumed, the same reaction happens at a much greater rate in the body due to β-glucosidase), causing acute symptoms.

Cyclo-
Cycloalkanes, CnH2n: 16.4.1.2
Examples of cycloalkanes
Cycloartenol, C30H50O
Cyclopropane, C3H6
Cyclobutane, C4H8
Cyclodiene
Cyclopentane, C5H10
Cyclohexane
Cycloheptane C7H14
Cyclooctane C8H16
Cyclovirobuxine, alkaloid
Cycloartenol
Cycloartenol, , C30H50O, pentacyclic triterpenoid, a 3beta-sterol, a phytosterol

Cycloastragenol,
Cycloastragenol, C30H50O5, sapogenin, pentacyclic triterpenoid, tetrol, oxolane
It is extracted from root of Astragalus membranaceus.

Cyclodiene
Alkenes, CnH2nolefins: 16.1.1.2
Cyclodiene pesticides, aldrin, chlordane, dieldrin, endrin, heptachlor: 16.4.01

Cyclohexanol
Cyclohexyl alcohol, HOCH(CH2)5, cyclohexanol, precursor to manufacture of nylon
Cyclohexanone
Cyclohexene, 3,4,5,6-tetra hydrobenzene, (old stock may form unstable peroxides), Toxic, Flammable
Cyclonite CH2N.NO2)3, Hexogen, cyclothrimethylene trinitramine, explosive, used with TNT
Cyclosilicates, Be3Al2(SiO3)6: Beryl

Cyclohexane
Cyclohexane, C6H12, flammable organic chemical: Cyclohexane
Cyclohexane, hexamethylene, hexahydrobenzene, colourless liquid, ethereal petroleum-like odour, Highly flammable, Toxic, in kohlrabi
It is used as a solvent, oil extractant, paint and varnish remover, and in solid fuels.
Cycloalkanes: 16.4.1.2
Cyclohexane, aromatic hydrocarbons, e.g.: Benzene, C6H6
Cyclohexane, octane number: See diagram 16.1.1h
Flammable liquids, cyclohexane: 3.5.8
Prepare nylon polymer: 3.4.7, .
Steam distillation to measure water and fat content of food: 10.5.5

Cyclohexanol
Cyclohexanol, C6H11OH, hexahydrophenol, cyclohexyl alcohol, hexahydrobenzene, hexalin, Toxic
Cyclohexanol, Solution < 20%, Not hazardous
Cyclohexanol, oily colourless liquid, Molal freezing point constant of cyclohexane solvent: 24.1.14

Cyclohexanone,
Cyclohexanone, C6H10O, 2,4-DNP Hydrazone, Toxic by all routes, flammable, use in skin and eye protection
Cyclohexanone, Solution < 1%, Not hazardous
Cyclohexanone, colourless liquid, odour like propane, cellulose lacquers, solvent

Cytosine
Cytosine, , C4H5N3O [4-Amino-2-hydroxypyrimidine], cytosinimine
It is pyrimidine base that is a fundamental unit of nucleic acids, is found in DNA and RNA that pairs with guanine
Cytosine, C4H5N3O, DNA and RNA: 9.4.0
Cytosine, Nucleic acid nitrogenous bases 3.0.0
See diagram, Heterocyclic compounds pyrimidines, cytosine

Cysteine
Cysteine, C3H7NO2S, L-cysteine, a thiol-containing non-essential amino acid that is oxidized in humans to form cystine
It is used as a flour treatment agent See diagram 16.3.6.0.1, Cysteine
E920, L-cysteine monohydrochloride
Cysteine, (Table of amino acids)
Cysteine, DNA codons

Cystine
Cystine, C6H12N2O4S2, L-cystine, (mirror image cystine), nonessential amino acid
It is formed by the oxidation of cysteine. (two molecules of cysteine are joined by disulfide bridge)>
It is used as a flour treatment agent.

Cytochromes
Cytochrome C, CYP, myohematin, hematin-protein, C42H52FeN8O6S2
CYP refers to enzymes in the liver and small intestines that use iron to oxidize harmful substances and drugs by making them more water-soluble, the process called "Phase I metabolism".
They may add a hydroxyl group then conjugation to groups such as glucuronide to increase the solubility even further, the process called "Phase 2 metabolism".
Cytochrome P450 catalysed reaction NADPH+ H + + O2 + RH--> NADP + + H2O + R-OH
(Where NADPH is a protein in the endoplasmic reticulum).
Also, CYP affects vascular autoregulation, in the brain and the formation of cholesterol, and steroids.
About 50 CYPs occur in humans.
Just as plants develop new alkaloids to limit their consumption by animals, animals develop new enzymes to metabolise the plant toxins.
Most CYP is anchored to membranes of the microsomal portion of the cell.
After adding an agent to reduce haem, part is exposed to carbon monoxide and if it strongly absorbs light at 450nm wavelength.
compared with the original solution, it must contain CYP, a process called "difference spectroscopy".