School Science Lessons
2024-12-24
Chemistry, Ca to Ch
Please send comments to: j.elfick@uq.edu.au
Contents
C.I. numbers, Pigment names
Cacotheline, (See: Tests for tin, 2.), (Experiment)
Cadaverine
Cadmium, Cd, (Experiments)
Caesium
Cafestol
Caffeic acid
Caffeine
Caffeotannic acid
Caffeoylputrescine
5-O-Caffeoylshikimic acid
Caffeoyl-D-glucose
Calactin
Calafatimine
Calamine, Smithsonite, (Geology)
Calcein
Calcination, plaster of Paris
Calcium, Ca
Carbon dioxide, Tests for
Calcofluor, Prepare,
Calebassine
"Calgon", Soften hard water using chemicals
Calico
Californium, Cf
Calmagite indicator, Test for water hardness, EDTA titration
Calomel, (Geology)
Calorie (See: Units of work and energy 3.)
Calorific value of fuel, Calorie, (Experiments)
Calorimeters, (Experiments)
Calotropin
Calystegin
Campesterol
Camphene
Camphor
Camphor oil, Prepare
Camptothecin
Can, beer can, beverage can
Canada balsam
Cancentrine
Candelilla wax
Candicine
Candimine
Candles
Candy, "Mentos" spearmint, Prepare CO2,
Cane sugar, Sucrose
Cannabisativine
Cannabinoids
Cannabis, Marihuana
Canola oil
Canola oil, (Table)
Canthaxanthin
Cantleyine
Caoutchouc, Latex, (Experiments)
Capillarisin
Capillin
Capric acid
Capric alcohol
Caproic acid
Capryl alcohol
Caprylic acid
Capsaicin
Capsanthin
Capsidiol
Captan, (Agriculture)
Caramelization, (Cooking), (Experiments)
Caranine
Carbohydrates, Molisch's test
Carat, (Measurement)
Carbamates
Carbamide, Urea, (Experiments)
Carbaryl
Carbetocin, Oxytocin
Carbides
Carbinol, Methanol
Carbohydrates, (Experiments)
Carbol fuchsin, Prepare,
Carbolic acid, Phenol
Carbol xylol, Prepare,
Calcium, (Experiments)
Carbon, Chemistry
Carbon, Geology
Carbon dioxide, CO2, (Experiments)
Tests for carbonates / bicarbonates
Carbon disulfide, CS2, (Experiment)
Carbon monoxide, CO, (Experiments)
Carbonated beverages, soft drinks, (Experiments)
Carbonates, (Experiments)
Carbonic acid, (Experiments)
Carbonyls,
Carborane
Carborundum
Carboxylic acids R-COOH, carboxyl group (-C(=O)-OH)R
Carboxystrictosidine
Carcinogenic substances
Cardenolide
Cardiac glycosides
Cardiopulmonary resuscitation, (CPR) and (EAR
Carene
Carmine, Carminic acid, Prepare,
Carnauba wax
Carnegine
Carnelian, (Chalcedony), (Geology)
Carnosol
Carnoy's fluid, (insect fixing), Prepare,
Carotenoids, Carotenes, Xanthophylls
Carpacin
Carpaine
Carrageenans
Carthamin
Carvacrol
Carveol
Carving stones, Limestone, (Geology)
Carvone
Caryophyllene
Cascarosides
Case-hardening
Casein, (Experiments)
Cassine
Cassiterite, (Geology)
Cassythicine
Castanospermine
Casticin
Cast iron
Castor oil, (Experiments)
Cat litter, (Geology)
Catalase, (Experiments)
Catalpol
Catalposide
Catalysts
Catalytic converter in a motor vehicle
Catechins, (Experiments)
Catechol
Catecholamines
Catharine
Cathine
Cathinone
Cathode, Anode,
Cathodic protection
Cation exchange capacity, (Agriculture)
Caulophylline
Caustic
Caustic baryta
Caustic potash, (Experiments)
Caustic soda, (Experiments)
Celadon, (Geology)
Cellophane, (Experiment)
Cellotape flags, (Experiment)
Celluloid, ping-pong ball, (Experiment)
Cellulose, (Experiments)
Celosianin
Celsian, barium feldspar, (Geology)
Celsius scale, oC
Cement, (Experiments)
Cementite, (See: 2.)
Cephaeline
Cepharanthine
Cereal, Breakfast, (Experiments)
Cerium, Ce
CERN, school experiments
Cerussite, (Geology)
Ceryl alcohol
Cetostearyl alcohol
Cetyl alcohol
Cetyl palmitate
Cevadine
CFCs, chlorofluorocarbons, "Freons"
CFCs, (See: 6.)
CFCs, "Freons",
CGS (cgs) units, (centimetre, gram, second)
Chaconine, Glycoalkaloids
Chain reaction, (Experiments)
Chalcanthite, (Geology)
Chalcedony, (Geology)
Chalcocite, (Geology)
Chalcopyrite, (Geology)
Chalk , (Geology), (Experiments)
Chamazulene
Change of state and solutions
Charantin
Charcoal, (Experiments)
Charcoal blocks, (Geology)
Charcoal, Activated charcoal
Charles's Law, (Experiments)
Chavicol
Chebulagic acid
Chebulinic acid, (Experiment)
Cheese-making, (Experiments)
Chelates, (Experiments)
Chelerythrine
Chelidonic acid
Chemical
Chemicals
Chemiluminescence
Chemistry
Chemotropic responses
Chevibetol
Chewing gum, Tg, (Experiment)
Chicle, (Experiments)
Cichoric acid
Chile saltpetre, (Experiments)
Chilli spray, (Agriculture)
Chitin
Clenbuterol
Chloral
Chloramines, in swimming pools
Chloramphenicol
Chlorate ion, ClO3-
Chlorates, Decomposition, (potassium chlorate):
Chlorates , Hazards, (potassium chlorate)
Chlordane, (pesticides)
Choleretic, increases bile from the liver
Chloric acid, HClO3
Chlorine, Cl
Chloro-compounds, (List)
Chloroacetic acid
Chlorofluorocarbons, CFCs, "Freons"
Chloroform, Trichloromethane, CHCl3
Chlorogenic acid
Chlorophenol red, acid-base indicator
Chlorophenols
Chlorophyll, chloroplasts: (Experiments)
Chloroplatinic acid
Chlorothalonil, (fungicide), (Agriculture)
Chocolate
Chocolate wrapper, (aluminium), in the mouth, (Biology)
Cholesterol, (Experiments)
Choline, (Experiments)
Chromatography, Separate by, (Experiments)
Chrome alum, Prepare
"Chroming", "huffing", (inhalant abuse)
Chromium, Cr
Chromite
Chondroitin sulfate
Chromate ion, CrO42-, dichromate ion Cr2O72-
Chrysanthemic acid
Chrysartemin A
Chrysanthenone
Chrysazin, Dantron
Chrysin
Chrysoberyl, alexandrite, Al2BeO4
Chrysolaminarin, β-1,3-glucan, in phytoplankton
Chrysoeriol
Chrysophanol
Chrysoprase, (Geology)
Chrysotile, Asbestos, (Geology)
Chymopapain, (Agricultue
Cadmium, Cd
See:CadmiumTable of the Elements
See:Cadmium, RSC
Cadmium, Cd (Latin cadmia calamine mineral, a zinc ore), lumps, rods, AAS solution, granular, powder
Highly toxic, Not permitted in schools, toxic at low concentrations.
Cadmium metal is soft silver-white or blue-white colour, shiny metal, usually combined with other elements, e.g. cadmium chloride, cadmium sulfite.
As a fine powder, it burns to release toxic fumes of cadmium oxide.
Cadmium is used for cadmium plating against corrosion, in nuclear reactors and in films sensitive to ultraviolet light, reference voltage in a Western Standard cadmium cell, Cd / Zn alloys in low melting point solders and aluminium solders, Ni-Cd batteries (Nicad), phosphorescent coating of TV tubes.
The artist's paint, cadmium sulfide, can be green, yellow and orange.
Cadmium looks like zinc, but make a crackling sound like tin when bent.
Oysters in polluted water may accumulate cadmium.
In former Communist countries, the practice of collection of "night soil" as a fertilizer, caused cadmium pollution of low-lying agricultural soil.
Cadmium is toxic, because it competes with Zn and Ca and can deprive the body of zinc by binding with proteins instead of zinc.
Large concentrations cause painful bone ailments and bone porosity in Japan, called itai-itai.
The human body gets rid of excess Cd by deposition in the kidneys and liver.
Atomic number: 48, Relative atomic mass: 112.41, RD 8.64, MP = 321oC, BP = 765oC.
Specific heat capacity: 230 J kg-1 K-1.
Cadmoselite, rare cadmium mineral containing cadmium (II) selenide, CdSe
Cadmium is used in metal plating and battery-industry stabilizing agents in polyvinyl chloride (PVC) products, alloyed with copper for automobile radiators, component of petrol, diesel fuel, lubricating oils.
Cadmium compounds
Cadmium and its compounds are stable, some compounds soluble, e.g. cadmium chloride, other compounds insoluble, e.g. cadmium oxide.
Cadmium acetate dihydrate, C4H6CdO4.2H2O, Cadmium acetylacetonate, C10H14CdO4, Cadmium bromide tetrahydrate, Br2Cd.4H2O
Cadmium carbonate, CCdO3, Cadmium copper, copper containing about 1% cadmium, is used in telephone lines.
Cadmium chloride, AAS Solution, cadmium chloride std, Not permitted in schools
Cadmium chloride anhydrous, CdCl2, cadmium chloride hydrate, CdCl2.xH2O
Cadmium chloride is used in the dyeing and printing of fabrics, in electronics component manufacture and in photography.
Cadmium disulfide, photosensitive semiconductor
Cadmium iodide, CdI2, white lustrous, flaky odourless crystals, becoming yellow in light and air.
Cadmium oxide, CdO, monteponite, "probable carcinogen", Not permitted in schools
Cadmium oxide is used in electroplating, in semiconductors, and in glass and ceramic glazes.
Cadmium (II) selenide, CdSe, cadmium (II) selenide, cadmoselite mineral, cadmium red, craft overglaze, "pigment red 108"
Cadmium (II) selenide, transparent to infrared light, photosensitive semiconductor
Cadmium (II) selenide, cadmoselite is a rare cadmium mineral containing cadmium (II) selenide, CdSe
Cadmium sulfo-selenide (cadmium red, red 108) Not permitted in schools
Cadmium sulfate (cadmium yellow, yellow 37), Cadmium sulfate hydrate, CdO4S.xH2O
Cadmium sulfide, CdS, craft yellow overglaze, cadmium yellow, pigment yellow 35, 36, semi-conductor, in light detectors
Cadmium sulfide (cadmium orange, orange 20, cadmium vermilion red), most colours, except blue
Cadmium sulfide is used in the electronics industry for photocells and light-emitting diodes, curing agent in tires.
Cadmium sulfide, greenrockite mineral, hawleyite mineral, insoluble in water
Cadmium telluride thin films in solar cells to replace silicon panels
Cadmium minerals:
Cadmoselite, CdSe, cadmium (II) selenide
Cadmium sulfide, CdS, greenrockite
Greenockite, CdS, cadmium sulfide mineral
Hawleyite, CdS, cadmium sulfide mineral
Cadmium reactions
Reactions of cadmium sulfate solution: 12.7.1
Heat substances with charcoal and fusion mixture: 12.11.3.8, (See: 4. Test for cadmium.)
Tests for cadmium: 12.11.3.15
Nickel-cadmium battery, NiCad battery: 33.1.8.5
Reactions of cadmium sulfate solution: 12.3.1
Weston Standard Cell, "Cadmium cell": 33.1.9
Caesium, Cs
See:CaesiumTable of the Elements
See:Caesium, RSC
Caesium (Cesium) Cs (Latin caesious blue-green, refers to spectral lines), caesium ion Cs+
Caesium melts in boiling water, caesium minerals, most electropositive and alkaline metal, MP 301.65 K.
Caesium 133 is used for very accurate atomic clocks, define the atomic second, in GPS technology.
Caesium has "sky blue" lines in its spectrum, Latin, caesium, colour of the sky
Discovered with spectroscope by Robert Bunsen and Gustav Kirchhoff in 1860
Caesium reacts explosively with water and may shatter the container.
2Cs + 2H2O --> 2CsOH + H2
caesium + water --> caesium hydroxide + hydrogen gas
Time, the "second", (Caesium 133 atom)
Caesium compounds
Cesium acetate, C2H3CsO2
Cesium bromide anhydrous, BrCs
Cesium carbonate, CCs2O3
Caesium sulfate
Caesium sulfate, Cs2SO4, cesium sulfate, dicesium sulfate, white pellets, large crystals, powder chunks, water soluble
It is used to prepare dense aqueous solutions, and is harmful if ingested.
Caesium trifluoroacetate
Cesium triiodide, CsI3
Caffeoyl-D-glucose
Caffeoyl-D-glucose, C15H18O9, (6-Caffeoyl-D-glucose), Glucosyl caffeate
It occurs in Solomon leaves, Datura leaves, Petunia flowers, and in Cestrum leaves.
N-Caffeoylputrescine
N-Caffeoylputrescine, C13H18N2O3, paucine, phenylpropanoid, phenolic compound
It occurs in Nicotiana tabacum flowers, Iochroma leaves, Pentaclethra seeds, and in Salix species
5-O-Caffeoylshikimic acid
5-O-Caffeoylshikimic acid, Dactyliferic acid, "date acid", C16H16O8, phenylpropanoid, carboxylic ester, a monocarboxylic acid
It occurs in dates Phoenixdactylifera, Butia, and in Tsuga.
Carboxyarabinitol 1-phosphate
Carboxyarabinitol 1-phosphate, C6H13O10P
Carboxyarabinitol 1-phosphate sugar alcohol, affects enzymes controlling diurnal regulation of plant metabolism.
It occurs in Phaseolus vulgaris leaves, in Glycine max, in Vigna, in Cucumis, in Nicotiana tabacum, in potato Solanum tuberosum.
Calcein
Calcein, C30H26N2O13, green fluorescent dye, used to determine calcium and label bones
Calico
Calico, "calico cloth" was imported from Calcutta, is now plain white unbleached unprinted cloth and unbleached semi-processed cotton.
It is used in bags, in buffing wheels, but, in North America, it is printed cotton cloth.
Californium, Cf
Californium, Table of the Elements
Californium, RSC
Californium was first made at "California University", radioactive, metallic actinide series
Campesterol
Campesterol, C28H48O, a phytosterol, component of plant cell membranes, inhibits absorption of cholesterol.
It is used to treat cardiovascular diseases, because of cholesterol-lowering and anti-carcinogenic effects.
It occurs in seed oil of
Brassica rapis, in wild mustard, in margarines, in vegetable oils, in seeds, in nuts, in fruits, in vegetables, in legumes, in beans, in avocados.
Canada balsam
Canada balsam from balsam fir, contains Pinene
Abies balsamea, Balsam fir
Prepare Canada balsam mounting solution: 6.1
Capillarisin
Capillarisin, C16H12O7, a coumarin, stimulate bile production, in Artemisia capillaris aerial parts
Capillin, C12H8O, aromatic ketone, an acetylene
Capric
Capric alcohol, 1-decanol, C10H22O, clear colourless liquid, sweet fat-like odour, insoluble in water
Capryl alcohol, 1-octanol, C8H18O, clear colourless liquid, aromatic odour, insoluble in water, floats on water, irritate eyes, nose
Carborane
Carborane, C2H2B10
A carborane called o-Carborane, C2B10H12, (1,2-Dicarbadodecaborane), in heat-resistant polyhedra clusters, causes convulsions, medical applications
Carboranes are heteroboanes, which have "organomimetic" properties
Carotenoids
1. Carotenoid pigments are tetraterpenoids from the acyclic parent carotene, and are produced from 8 isoprene molecules.
They have 40 C atoms, in two six-carbon rings connected by a chain of carbon atoms.
2. Carotenoids are red, orange and yellow, fat-soluble, insoluble in water, plant and animal organic pigments in plants, algae, fungi and bacteria.
3. Presence of carotenoids is shown by the bright red, orange and yellow pigments.
In beet greens, broccoli, cantaloupe, carrots, collard greens, green peas, kale, leafy green vegetables, mango, okra, oranges, papaya, parsley, pink grapefruit,
pumpkin, red peppers spinach, sweet potatoes.
Swiss chard, tangerines, tomatoes, watermelon, winter squash, and fish liver oil.
4. Carotenoids should be ingested with fats in the diet and are stored in fatty tissue, may be antioxidants.
A high carotenoid diet may help reduce the risk of lung cancer in non-smokers and breast cancer.
Most carotenoids are not damaged by cooking.
5. Carotenoids absorb blue and green wavelengths of light causing yellow and orange colours.
Carotenoids occur in chromoplasts, which show when fruit is ripe, and in chloroplast membranes to absorb light energy for photosynthesis.
They are accessory pigments and protect chlorophyll from damaging wavelengths.
The most common carotenoids in food are alpha-carotene, beta-carotene, beta-cryptoxanthin, lutein, zeaxanthin, and lycopene.
6. Provitamin A carotenoids, alpha-carotene, beta-carotene, and beta-cryptoxanthin, can be converted to retinol (vitamin A).
Lutein and zeaxanthin, in the macula of the eye, absorb most incident blue light, and may prevent age-related macular degeneration.
Carotenes, Xanthophylls
Tetraterpenes, C40, 40 carbon atoms, (eight isoprene units), (Isoprene unit: C5H8, CH2=C(CH3)−CH=CH2)
Isoprene units
* 1.0 Carotenoids, (yellow, orange, red pigments)
Carotenoids
* 1.1 Carotenes, C40Hx. no oxygen, orange or red pigments
Carotenes are hydrocarbon carotenoids, a subclass of tetraterpenes and C5n polyterpenes, C40Hx
Plants rich in carotenes include, sweet potato (red variety), kale, (carrot, mustard greens, spinach driedbasil, butternut squash, lettuce (red leaf variety).
List of carotenes
* 1.2 Xanthophylls, contain oxygen, yellow or brown oxygenated carotenoids, carotene derivatives
Xanthophylls
Zeaxanthin, C40H56O2., xanthophyll
Boiling, test the cooking water of boiled vegetables:19.2.12, (See 1. and 6.)
Chromatography of chlorophyll pigments:10.2.1 (See: 3.)
Lutein
Lycopene
Vitamin A:9.6.1 (See: Carotenes)
List of carotenes
* Alpha-carotene (α-carotene), C40H56, carotenoid pigment, Vitamin A precursor, are used as yellow food colouring, in green leaves of many plants.
They occur in in carrot roots, in maize seed, in oil palm and in tomato.
* Beta-carotene (β-carotene), C40H56, carotenoid pigment, Vitamin A precursor, wide occurrence most green leaves and coloured fruits and vegetables
They are used as yellow food colouring of fats, e.g. margarine, used as sunscreen, red-purple oil, not soluble in water, in dark orange varieties of sweet potato.
β-Carotene, Type II, synthetic, 95% (HPLC), crystalline, β, β-Carotene, Provitamin A, C 40 H 56, commercial
* Gamma carotene (γ-carotene), C40H56, carotenoid pigment, Vitamin A precursor
E160e, Beta-apo-8' carotenal
E160f, Ethyl ester of beta-apo-8
Delta-carotene, Zeta-carotene
β-carotene) 5,6-epoxide
β-Carotene, Type I, synthetic, 93% (UV), powder, β, β-Carotene, Provitamin A, C40H56
β-Carotene, Type II, synthetic, 95% (HPLC), crystalline, β, β-Carotene, Provitamin A, C40H56
Carotene epoxide, zeta-Carotene epoxide, (1,2-Epoxy-1,2-dihydro-z-carotene), C40H60O, occurs in garden tomato,
and in cherry tomato, (Solanum lycopersicum var. cerasiforme).
Casein
Casein, , C81H125N22O39P, (Latin caseus cheese), about 3% of milk and essential for cheese.
Casein is a mixture of phosphoproteins and is a lyophilic colloid, like albumin and gelatin.
Casein is a globular protein.
Casein, milk casein, casein plastic, (artificial horn), thermoset plastic
Casein formaldehyde was made from milk, soy beans, wheat, may look like celluloid or artificial horn, was used to make buttons, umbrella handles.
Casein, thermoset plastics:3.5.6
Casein and caseinates, Milk proteins:16.3.0
Cheese making:16.2.4
Clot on boiling test, (C.O.B. test):16.1.2
Fibrous proteins and globular proteins:16.6.0, (See: 2. Globular proteins)
Prepare casein plastic from milk:3.3.5
Milk casein, phosphoprotein thermoplastic polymer, for insulators, buttons, handles, adhesives, artist's priming paint
Prepare urea-formaldehyde resin:3.3.12, (See: 2.)
Regular cows milk, fresh milk, full cream milk, whole milk:16.2.1a
Size of colloidal particles:11.3.0, precipitate casein
Tests for synthetic fibres, burning test. casein:4.3.2
Catalase
Catalase is a common enzyme in animal and plant cells that catalyses the decomposition of hydrogen peroxide to water and oxygen.
Catalase occurs in almost all aerobically respiring organisms and serves to protect cells from the toxic effects of hydrogen peroxide and
promotes the growth of some cells in the human body.
Catalase is a heme enzyme that is present in the peroxisome of nearly all aerobic cells.
Catalase is a key antioxidant enzyme in the bodies defense against oxidative stress.
Catalase converts the reactive oxygen species hydrogen peroxide to water and oxygen and thereby mitigates the toxic effects of hydrogen peroxide.
Oxidative stress is hypothesized to play a role in the development of many chronic or late-onset diseases such as diabetes, asthma, and cancers
12.6.3, Bleaches in washing powders
19.2.12, Boiling, test the cooking water of boiled vegetables, (See 7.)
17.7.16, Hydrogen peroxide with catalase in raw beef liver
17.7.17, Hydrogen peroxide with catalase -.Disproportionation
17.7.10, Hydrogen peroxide on cut potato
17.7.9, Hydrogen peroxide on cut skin
17.7.20, Hydrogen peroxide with yeast, elephant's toothpaste reaction
9.3.23, Test for zymase and catalase in yeast
Catalysts
Catalysis, catalysts: 17.3.0 (Experiments)
Alumina as a catalyst in the cracking process: 12.3.1
Browning reactions of fruits and vegetables: 19.2.3.1
Bleaches in washing powders: 12.6.3
Catalysis, (List)
Catalytic conversion of nitric oxide: 3.44.1
Catalytic converter in a motor vehicle: 18.6.1
Catalytic cracking of kerosene: 10.3.8
Cracking, Thermal cracking, Catalytic cracking
Catalytic oxidation of ammonia, with red-hot platinum wire: 13.6.6.1
Catalytic oxidation of ammonia, with chromium (III) oxide: 13.6.6.2
Prepare oxygen gas with hydrogen peroxide: 3.49.0, manganese (IV) oxide
Propane C3H8, (catalytic cracking): 16.6.2.0
Catechins
Catechins, flavonoids, from catechu, Mimosa catechu, (Acacia catechu)
The four catechin isomers:
Two trans isomers called catechin [(+)-catechin and (-)-catechin], and two cis isomers called [(+)-epicatechin and (-)-epicatechin]
.
(+)-Catechin and (-)-epicatechin occur in food plants.
(-)-Epicatechins and their derivatives occur in green tea.
(-)-Catechin, C15H14O6
Catechins are from polyphenolic antioxidants with phytotonic properties, and are used for treating obesity.
Dark chocolate and red table wine contain high concentrations of catechins and their compounds,
Racemic catechin is used to study seed germination and plant invasion
The most common catechin isomers are (+)-catechin, called catechin, and (-)-catechin, called epicatechin (entcatechin).
Catechins occur in many plant species, e.g. Cinnamomum kotoense,
See diagram 16.21.6, Catechin
Epicatechin
Flavanols, Flavan-3-ols,
1. Monomers - catechin, in chocolate, cinnamon, in red wine, green tea, cocoa, argan oil.
It is used as haemostatic drug to treat liver diseases.
(+)-Catechin 3-O-glucose, C21H24O11
Catechin 7-O-beta-D-xyloside, C20H22O10, is a monosaccharide derivative of catechin.
Cinnamtannin A2 C60H50O24
Catechins, green tea, grapes
Catechin gallate.
Catechin hydrate.
EpicatechinH, (EC), Flavonoid.
Catechin gallate
Catechin hydrate
Epicatechin, (EC), Flavonoid
ECG Epicatechin gallate (ECG), Flavonoid.
EGC Epigallocatechin, Bioflavonoid.
EGCG Epigallocatechin gallate, Bioflavonoid
Catechol
Catechin gallate, C22H18O10
Catechin gallate, bioflavonoid, green tea extract, antioxidant, free radical scavenger, may treat breast cancer
(2S,3R)-2-(3,4-Dihydroxyphenyl)-3,4-dihydro-1(2H)-benzopyran-3,5,7-triol 3-(3,4,5-trihydroxybenzoate)
Catechin hydrate, C15H14O6.xH2O
(+)-Catechin hydrate, polyphenolic antioxidant, Chinese medicine, antioxidant, free radical scavenger, suppresses DNA strand breaks
Caprylic acid, C8H16O2
Caprylic acid, Octanoic acid, straight-chain and medium-chain saturated fatty acid, colourless to light yellow liquid, mild odour, burns, but difficult to ignite.
It is corrosive to metals and tissue, antibacterial agent, and occurs in milk of mammals, coconut oil, and palm kernel oil
Catharanthine, C21H24N2O2
Catharanthine, terpene indole alkaloid, in Catharanthus roseus
It is hypoglycaemic, dilates small mesenteric arteries, decreases heart rate and cardiac contractility, and occurs in Vinca rosea
Caustic
A caustic substance is very alkaline, with pH approaching 14.
It can dissolve skin and fat to form soap, e.g. caustic soda NaOH, caustic potash KOH
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).
Cellophane absorbs moisture, is used in children's item "Fortune Telling Fish".
Experiment
9.1.1 Cellophane as a semipermeable membrane
Cellulose, (C6H10O5)n
Cellulose, cellulose ashless, cotton wool, hemicellulose, lignin
Cellulose (MTA)
9.214, Cellulose digestion, (Biology)
16.3.1.6, Cellulose, hemicellulose, (Biology)
9.214, Cellulase, Cellulose digestion
3.4.03, Cotton
4.3.10, Micro-organisms and cellulose
9.142.6, Tests for cellulose, Fehling's solution
9.3.8, Tests for cellulose
9.3.22, Tests for wood,
Cellulose compounds
Celluloid film (cellulose nitrate + camphor)
Cellulose acetate:3.5.8
Cellulose acetate sheet:31.1.23
9.214, Cellulose digestion
Cellulose nitrate (nitrocellulose, guncotton)
Celluloid:3.5.7
Cellulose nitrate:3.5.9
Collodion, cellulose nitrate:3.5.10
Cellulose propionate, cellulose butryate, ethyl cellulose
Triboelectric series, electrostatic series, ranking of insulators:31.1.02, (See 17. Cellulose acetate)
Diethyl ether
Ethyl cellulose, burning test for synthetic fibres:3.102
Prepare rayon, basic copper carbonate with ammonia solution:3.4.8.1
Prepare rayon, copper (II) sulfate with ammonia solution:3.4.8.0
Tests for plastics, natural fibres and synthetic fibres:3.102
Tests for polymers:4.0.0
Cerium, Ce
See:Cerium, Table of the Elements
See:Cerium, RSC
Cerium, Ce (Ceres asteroid discovered just before Ce discovered by Jacob Berzelius, Sweden.
It is the most abundant rare earth, but future supply shortfall.
It is found with Lanthanum.
Cerium is used in cast iron, steel, aluminium alloys.
Cerium-iron alloy, "Auermetall", mischmetal cigarette lighter ignition flints.
Cerium, in mischmetal (German, mixed metal), cigarette lighter ignition flints.
Cerium components of rare earth elements mixture.
Cerium oxide, is used in jeweller's rouge gemstone abrasive, sweet tasting cerium salts.
It was formerly used in anti-emetic medicines, cough mixtures, now is used in diesel fuel, film set lights.
Cerium sulfate
Cerium (III) sulfate, Ce2(SO4)3, ceric sulfate, also hydrated forms, yellow to orange solid / crystals
Cerium (IVI) sulfate, Ce(SO4)2, ceric sulfate, also hydrated forms, yellow solid / crystals
Cerium (IV) ammonium sulfate
Cerium chloride, CeCl3
Cerium chloride, cerium (III) chloride heptahydrate, Harmful if ingested
Cerium sulfate, Harmful if ingested
Monazite CePO4
Cetyl alcohol, C16H34O
Cetyl alcohol, Hexadecan-1-ol, (1-Hexadecanol), Palmityl alcohol, C16H34O, CH3(CH2)15OH, waxy white solid powder, fatty alcohol, non-ionic surfactant.
It is used as emulsifying agent in pharmaceutical products, long chain primary fatty alcohol.
It was originally produced from whale oil, but now produced from palmitic acid, waxy white powder or flake form, insoluble in water.
in cosmetic products as opacifier, emulsifier, thickening agent, increase foaming capacity, is used to drying of skin [A32209] and skin protectant.
Toxic by all routes, highly flammable
Cetyl alcohol forms the ester cetyl palmitate C15H31.COO.C16H33, m.p. 42oC to 47oC.
It is the main component of spermaceti, white wax from the head of the sperm whale.
The wax was used to make cosmetics and ointments, but nowadays we use other chemicals as substitutes to "Save the Whales"!
Melting point of substances:7.4.2.0
Ceryl alcohol, 1-hexacosanol, C26H54O, very long-chain primary fatty alcohol,
Cetostearyl alcohol, C34H72O2, waxy white solid, soapy odour, floats on water
Chain reaction
A chain reaction is where one chemical reaction causes further chemical reactions.
Neutrons from an atom collide with other atoms to break them up and emit more neutrons, leading to atomic explosion.
Chain reaction, Sodium acetate heat pack:14.1.11
Chain reaction, DNA and RNA:4.4.0
Chelates
Chelates, sequestrant:19.1.0.1
Chelating agents, sequestering agent:18.1.18, (Swimming pools)
Diaminoethane, ethylene diamine, C2H4(NH2)2,
ligand, chelating agent, Toxic by all routes, Corrosive
Ethylenediamine (en), bidentate ligand
Tests for metal ions in water, EDTA, chelates:12.13.11
Chelidonic acid, C7H4O6
Chelidonic acid, Jervasic acid, irritant, carbonyl compound, pyran, in Chelidonium majus
Potassium chelidonate controls nightfall closing of leaves of Cassia mimosoides
Chemical
Chemical reactions
ChemicalChemistry files, (in this website)
Chemical bonds, (single, double, triple)
Chemical bonds11.21
Chemical equilibrium17.5.0
Chemical fertilizers, fertilizer trial9.17.0
Chemical fertilizers6.34, (Year 6, Primary School)
Chemical, Quantity of chemical to be used in experiments3.4.2, (5 mL of solution, or ...)
Chemical reactions12.2.0, (Types of chemical reactions)
Chemical reagents, Prepare reagents, Table10.0
Chemical residues3.3.0
Chemical Safety
Chemical sources of polymer materials:3.4.02
Chemical Standards National Formulary, NF
Chemistry terminology, Chemical changes and physical changes, Prepare sulfur
Tests, Chemical tests
Chemical vapours and smelling chemicals3.4.8
Chemical weathering reactions35.22.4.01, (Geology)
Prohibited High Risk Chemicals
Chemicals
Chemicals, Abbreviations, Chemistry
appendixB, Biology preparations
Chemicals, Biology, Chemicals, Preparations
Chemicals, Lists of chemicals5.0, (Acids, Adhesives, Alcohols ...)
Chemicals, Low-cost chemicals and common substances:16.0.0
Chemicals, Lists of chemicals
Chemicals, Phytochemicals
Chemicals Not permitted in schools15.10.0, (in NSW, Australia)
Chemicals:Organic Chemistry, (terms, properties, tests)
Chemicals, Pigment names, C.I. numbers (Table)8.0
Chemicals:Prepare, chemicals
Chemicals safety3.4.0
Chemicals spill kit3.4.12, (contents)
Chemicals, Storing chemicals3.4.13
Chemicals swallowed3.4.7, (Safety)
Chemicals used in swimming pools18.1.0
Prepare chemicals
Chemistry
Chemistry, Websites
Chemistry files, (in this website)
Chemistry of natural products
Chemistry, (Primary)6.0
Chemistry terminology7.9.0, (Acid, acids, Aerobic, Aliquot ...)
6.3.0, Soil chemistry
Prepare
Prepare, chemical substances
1.0, Prepare acids and bases
5.3.3, Prepare alkalis
3.32, Prepare gases
6.0, Prepare known concentration solutions
10.0, Prepare reagents (Table):
2.0, Prepare salts
4.0, Prepare serial dilutions
5.2.0, Prepare serial dilution, different % concentrations
3.0, Prepare solutions
7.0, Prepare solutions of salts, salt solutuons
5.0, Prepare stock solutions
5.1.6, Preparation instructions, calculation:
Chemical bonds
Single bond, --, double bond =, triple bond, e.g. carbon monoxide, C≡O
Chemical bonds:11.01.0
11.01.8, Bond energy (bond strength)
Liquids with different viscosity, hydrogen bonds:11.01.9
Tomato sauce, ketchup, catsup:13.6.4
Water stream from a tap, faucet:13.4.9
Chemical reactions
Reactions of, (chemicals)
Chemical reactions, types of chemical reactions:12.2.0
Common ion effect, sodium ethanoate and ethanoic acid:17.5.2
Concentration and temperature, cobalt (II) chloride-6-water:17.5.1
CP, (Chemically Pure), general applications, chemicals standard
Disposal of waste chemicals:3.4.11
Effect of temperature on chemical equilibrium:17.5.5.5
Energy from chemical reactions:3.80
Functional groups:2.0
Handling and transferring chemicals:3.4.10, (safety)
Hazards, (chemicals classification)
Health effects of chemicals:3.0
Health hazards:5.0.0
High toxicity chemicals:4.6.02
Household chemicals, chemicals in the home:19.1.0
Laboratory safety and hazardous chemicals:4.0
Lists of chemicals:5.0
Physical hazards:4.0.0
Prepare, (chemicals)
Prepare reagents:10.0
Prepare solutions of known concentration:5.4.0
Prepare stock solutions:5.3.0
Quantity of chemical to be used in experiments:3.4.2
Chicle
3.4.01, Glass transition temperature (Tg), chewing gum, cotton
23.6.2, Latex plants
Manilkara achras
Polyterpenes, (many isoprene units)
16.7.30, Tests for chewing gum quality by comparing bubbles
Cichoric acid, C22H18O12
Cichoric acid, an hydroxycinnamic acid, inChicory, (Cichorium intybus), dandelion leaves, basil,
lemon basil
Chloric acid, HClO3
Chloric acid, chloric (V) acid, Harmful if ingested, explosive with organic compounds, Not permitted in schools
Chloric acid, dangerous powerful oxidizing agent. Conc. sulfuric acid+ (potassium chlorate + sucrose) --> chloric acid
Chloric acid, HClO3, chloric (V) acid, or any of the oxyacids of chlorine, including the following,
Chloro-compounds, organic
Chlorous acid, HClO2, chloric (III) acid
Hypochlorous acid, HOCl, chloric (I) acid
Perchloric acid, HClO4, chloric (VII) acid
Chloroacetic acid, CH2ClCOOH
Chloroacetic acid, chloroethanoic acids, mono-, di- and tri-, Toxic, vapour highly irritant to lungs, skin
Chloroacetic acid, chloroethanoic acid, monochloroacetic acid, (use small quantities < 10 mL)
Chloroacetic acid, solution < 0.2%, Not hazardous
Organic builders in washing powders:12.12.03.2b
Oxyacids, oxoacids:13.3.6
Saturated carboxylic acids:16.3.8.1
Chlorophenols
Chlorophenol red (acid-base indicator):9.0
Phenols:16.1.3.2
See diagram 16.1.4.4, 2,4,6 trichlorophenol
There are 19 different chlorophenols.
On combustion chlorophenols form toxic and corrosive gasses.
Upon heating, toxic fumes are formed.
Chlorophenols reacts violently with strong oxidants.
Most chlorophenols are solids, usually as needles and flakes, have strong medicinal taste and odour.
Their melting temperatures increase with number of chlorine atoms.
2,4,6-trichlorophenol is found most frequently in water near hazardous waste sites.
In sewage plants, chlorophenols are usually broken down by the bacteria.
Exposure to concentrated forms of these compounds include severe irritation and burns of the skin.
Some chlorophenols are carcinogens
Chloroplatinic acid, H2PtCl6.6H2O
Chloroplatinic acid, hexachloroplatinic acid hexahydrate, H2PtCl6.6H2O,
or [H3O]2[PtCl6]4H2O, [platinic chloride PtCl4], (dust may trigger asthma, skin sensitivity)
Chloroplatinic acid hydrate, platinic chloride, H2PtCl6.xH2O
Cholesterol, C27H46O
Cholesterol (MTA)
Cholesterol:3.9.1
Cholesterol and fat in eggs:13.2
Enjoy eggs every day!13.7, (See: 2.)
Glycaemic index, (GI), ("good cholesterol")
Flavonoids, (prevent bad cholesterol)
16.9.18, Statins, cholesterol-lowering drugs:
Wool wax
Choline, C5H14NO
Choline cation, C5H14NO+, neurotransmitter, human nutrient, occurs in many plants and animal organs, a precursor of acetylcholine
Nutritional value of eggs, wherebone large egg is 50 g., Choline 225 mg
Choline: 16.1.7
Choline: 16.7.21.1
Enjoy eggs every day! 13.7, (See: 2.)
Nutritional value of eggs: 22.20
Phospholipids (phosphoglycerides): 16.1.10
Chondroitin sulfate
Chondroitin sulfate is found in cartilage around joints in the human body.
It can be made from shark cartilage and cow cartilage
Chondroitin sulfate, acidic mucopolysaccharides, glycosaminoglycans are long unbranched polysaccharides, repeating disaccharide units
Chondroitin sulfate proteoglycans = protein core + chondroitin sulfate, in cartilage, may relieve osteoarthritis
Chondroitin sulfate sodium salt from bovine cartilage
Chromium, Cr
See: Chromium, Table of Elements
See: Chromium, RSC
Chromium, Cr, (Greek khrōma colour, from coloured compounds), white, hard, lustrous and brittle metal.
It is extremely resistant to ordinary corrosive agents.
It is a reactive transition metal, but forms protective oxide layer in air that prevents further oxidation and forms hard alloys with Ni or Fe.
Chromium is available as technical grade chromium, is extracted from chromite, (Fe(CrO2)2).
It is used for chromium plated metal, hard plating Cr2O3, catalysts, in stainless and heat-resistant steel.
Strong reducing agent Cr2+ salts blue in aqueous solution, Cr3+ salts green in aqueous solution.
CrO42- salts yellow, e.g. potassium chromate, K2CrO4.
It is a strong oxidizing agent Cr2O72-, orange, e.g. potassium dichromate, K2Cr2O7.
Chromium deficiency reduces tolerance to glucose.
Chromium, Cr, metal, AAS Standard, lumps, coating grit, chips, powder
Chromium-151, reactor-produced medical radioisotope, half-life 27.7 days, used to label red blood cells
Chromium (II), Cr2+, strong reducing agent, blue salts in aqueous solution
Chromium (III), Cr3+, green salts in aqueous solution
Atomic number: 24, Relative atomic mass: 51.996, RD 7.19, MP = 1890oC, BP = 2482oC.
Specific heat capacity: 448 J kg-1 K-1.
Chromite, FeCr2O4
Chromium oxychloride
Chromium plating, electroplating:15.1.3
Chromium toxicity:4.6.5
Reactions of chromium compounds:12.5.0
Tests for chromium:12.11.3.17
Tests for chromates:12.11.5.9
Chromium compounds
Chromium (III) compounds, very small quantities of chromium (III) compounds are essential for health and well-being
Chromium (VI) compounds are usually highly toxic, soluble in water and solutions are powerful oxidizing agents in acidic conditions.
However, it is less oxidizing under alkaline conditions
Calcium chromate, CaCrO4, yellow powder, slightly soluble in water
Chromium salts, Chromium, chromic acid toxicity:3.6.5
Chromous salts are chromium salts in the (II) oxidation state, form blue solutions
Barium chromate, BaCrO4
Chromates
Chrome alum, K2SO4.Cr2(SO4)3.24H2O
Chrome iron ore, FeCr2O4, chromite
Chrome red, PbO.PbCrO4, basic lead chromate
Chrome yellow, PbCrO4, lead chromate pigment
Chromic (III) sulfate
Chromic acid
Chromic nitrate, chromic nitrate hydrated, chromium (III) nitrate nonahydrate
Chromic potassiumsulfate, KCr(SO4)2.12H2O
Chromite
Chromium hexacarbonyl, C6CrO6
Chromium (II) acetate, dimer monohydrate, C8H16O10Cr2
Chromium (II) chloride, chromic chloride, Cl2Cr
Chromium (II) oxide, CrO, insoluble black powder
Chromium (III) acetate, chromium (III) ethanoate, chromic acetate, chromium acetate, Harmful if ingested
Chromium (III) chloride, Cl3Cr
Chromium (III) chloride hexahydrate, Cl3Cr.6H2O
Chromium (III) hypochlorite
Chromium (III) nitrate, (CrN3O9, green crystals, very soluble in water), is used in pickling.
Chromium (III) nitrate nonahydrate, Cr(NO3)3·9H2O, CrN3O9.9H2O, [Cr(H2O)6](NO3)3•3H2O, red-violet crystals, very soluble in water
Chromium (III) oxide
Chromium (III) phosphate, CrH8O8P, Chromium (III) phosphate tetrahydrate
Chromium (III) potassium sulfate dodecahydrate, CrKO8S2.12H2O
Chromium (III) sulfate
Chromium (IV) oxide, CrO2, insoluble black powder
Chromium (VI) oxide, chromium trioxide, CrO3
Chromium oxychloride
Chromium potassium sulfate
Copper-chromium alloys:5.5.14
Dichromates
Oxidize chromium compounds to chromates, CrO42-:12.5.5
Prepare potassium dichromate, K2Cr2O7:12.5.6
Potassium chromate, K2CrO4
Potassium chromium sulfate, KCr(SO4)2.12H2O
Potassium dichromate, K2Cr2O7
Reactions of chromates, CrO42-:12.5.4
Chromium, Reactions of chromium, Cr, and chromium compounds:12.8.0
Reactions of dichromates, Cr2O72-, potassium dichromate:12.5.3
Tests for chromates:12.11.9
9.0 Chlorophenol red, acid-base indicator
Chlorophenol red (dichlorophenolsulfonephthalein), C19H12Cl2O5S
pK: 6.25
pH colour change: 4.8-6.4
Acid: yellow, Base: red
It can detect chlorine dioxide in drinking water, green to brown-green or brown powder, crystalline powder, crystals, granules or lumps
It is soluble in ethanol, and has a "pharmacy smell".
Chromates
Chromates, -CrO42-, usually yellow salts
Chromates, dichromates, hazards:3.7.4
Movement of copper and chromate ions:33.89
Reactions of chromates:12.5.4
Tests for chromates:12.11.5.9
Chrome alum, K2SO4.Cr2(SO4)3.24H2O, CrK(SO4)2.12H2O
Alums
Prepare chrome alum:12.14.4.0
Chrome alum (properties):12.14.4.1
Chrome alum, chromium (III) potassium sulfate, chromium potassium sulfate dodecahydrate, potassium chromium (III) sulfate dodecahydrate.
It, is used for tanning, mordant,
photography, purple or violet-red octahedral crystals
Chromic acid, H2CrO4
Chromic acid, Not permitted in schools
Do not prepare or use in a school science laboratory!
Cleaning agents, "chromic acid":2.20.3
Ionization reaction, H2CrO4:12.5.7
Chromic acid, H2CrO4, exists only as salts, e.g. lead chromate, barium chromate, or in solution
Chromic acid, H2CrO4, Highly toxic if ingested, Not permitted in schools
Chromic salts are green-violet chromium salts in the (III) or (VI) oxidation state
Chromic acid, very reactive (conc. sulfuric acid + dichromate --> formerly used as a glass cleaning solution).
Chromium (III) oxide, Cr2O3
Chromium (III) oxide, chromium oxide, chromium trioxide, chromic oxide, chrome green, chromia, green chromium oxide
Chromium (III) oxide, chromium sesquioxide, an amphoteric oxide (C.I. pigment Green 17), Highly toxic if ingested, is used for craft.
Catalytic oxidation of ammonia, with chromium (III) oxide:13.6.6.2
Prepare chromium trioxide:12.5.2
Chromium (VI) oxide, CrO3
Prepare chromium trioxide, CrO3:12.5.2
Storing chromium (VI) oxide:3.4.13.3
Chromium (VI) oxide, Not permitted in schools, Highly toxic if ingested, carcinogenic
Chromium (VI) oxide, chromium trioxide, CrO3, (chromic acid anhydride), Toxic, dark red powder
Chromium (VI) oxide was formerly a glass cleaning solution called "chromic acid".
It is prepared by mixing a metal chromate or dichromate with concentrated acid in a chromate salt solution.
However, this solution is dangerous and other glass cleaning detergent solutions should be used.
Chromium (VI) oxide, forms explosive mixtures with combustibles or organic compounds.
Chromic trioxide is a powerful oxidizing agent.
Sold as Chromic acid, polymer-supported.
Do NOT use chromic acid for glass cleaning in school science laboratories.
Chromium (VI) oxide, CrO3, chromium trioxide, chromic acid anhydride, strong oxidizing agent
Chromium (VI) oxide, chromic anhydride, glass cleaning solution
Chromium trioxides are soluble in alcohol, ethanol, sulfuric acid, and nitric acid.
When heated to decomposition, chromium trioxides emit smoke and irritating fumes.
Chromium trioxide, Jones reagent, chromium trioxide in dilute sulfuric acid for oxidation of organic substances.
Chromium oxychloride, CrO2Cl2
Chromium (VI) oxychloride, dichlorochromium (VI) oxide, chromyl chloride, Highly toxic by all routes, strong red oxidizing liquid, Not permitted in schools
Chromyl chloride, Solution < 1%, Not hazardous
Chromium (III) sulfate, Cr2(SO4)3
Chromium (III) sulfate, chromium sulfate, chromic sulfate, Harmful if ingested
Chromium sulfate, Cr2(SO4)3, Cr2O12S3, dark green to violet crystals, is used in paints, inks, ceramics, dyeing, non combustible, environmental damage.
Chromium (III) sulfate, Cr2(SO4)3.x(H2O), violet-green "basic chromium sulfates"
Cr2(SO4)3, Cr2(SO4)3.18H2O, Cr2(SO4)3.15H2O
Chromite, FeCr2O4
Chromite, iron chromium oxide, iron chromite, chrome iron ore, chromium ore, chrome iron ore, occurs in basic igneous, metamorphic and sedimentary rocks.
It is dark grey to black colour, metallic lustre, specific gravity 4.0 to 5.1, Mohs scale hardness 5.5 to 6, brown streak.
It is slightly magnetic, so may be confused with magnetite,
It is the only economic ore of chromium, magnesium substitues for iron in molecule in significant amounts.
Chromium in Cr (III) form, as mineral chromite, FeCr2O4, iron chromium oxide, iron chromite, chrome iron ore
Chromone, C9H6O2
Chromone, (4-Chromone), simplest member of the chromones
It occurs in fats and oils, and in Isol from Ye Hao (Carum carvi)
Chrysophanol, C15H10O4
Chrysophanol, Chrysophanic acid, (3-Methylchrysazin), Turkey rhubarb, trihydroxyanthraquinone, irritant, antiviral, anti-inflammatory
It appears as golden yellow plates or brown powder.
It is used as a natural dye, to control termites in teak wood.
It occurs in Rumex, Rheum, Aloe vera, teak wood, and in senna leaves Cassia senna.
See diagram 16.3.1.4E, Chrysophanol
Chrysin, C15H10O4
Chrysin, a flavone, (5,7-Dihydroxyflavone), Chrysine, (7-hydroxyflavonol), flavone, anti-inflammatory, antineoplastic, antioxidant, hepatoprotective.
It occurs in carrot, in honeycomb, Oroxylum indicum, Passiflora caerulea, Matricaria chamomilla, and Oroxylum indicum.
See diagram 16.3.1.4E, Chrysin
Chrysin dimethyl ether, (5,7-Dimethoxyflavone), Dimethylchrysin, C17H14O4, dimethoxyflavone, is a 5,7-dimethyl ether derivative of chrysin.
It occurs in Leptospermum scoparium.
Chrysoeriol, C16H12O6
Chryseriol, (3'-Methoxyapigenin), (Luteolin 3'-mether), (3'-methoxyflavone), trihydroxyflavone, a widespread flavone, antineoplastic, antioxidant,
It occurs in alfalfa
3.71.5, Chalk, School chalk, blackboard chalk, safety
The chemicals in blackboard chalk, mainly gypsum, CaSO4.2H2O, are harmless if ingested.
However, chalk dust may cause respiratory problems in children with asthma, and in teachers after exposure for many years.
The new product called "dustless chalk" is chemically the same, but the chalk dust it produces consists of much heavier particles that quickly drop down instead of being suspended in the air.
Chalk dust should be regularly cleaned out of the classroom .
Chalk dust may damage electronic equipment, e.g. computer motherboard and playback heads of VCRs.
Yellow chalk on a green "blackboard" may be more visible to most students, but may cause problems for colour-blind students.
3.71.6, Solubility of school chalk, blackboard chalk, in water
Shake powdered blackboard chalk (school chalk), mainly gypsum, CaSO4.2H2O, with water in a test-tube.
Filter the mixture and collect the filtrate in an evaporating basin.
Evaporate the water by heating the evaporating basin over a beaker of boiling water.
Examine the inside surface of the basin.
If any residue is found, then some chalk is soluble in water.
3.71.7, School chalk, blackboard chalk with weak acids
Put three sticks of blackboard chalk, mainly gypsum, CaSO4.2H2O, in beakers partly filled with water, lemon juice, vinegar, so that about half of each stick is still dry.
Observe the chalk sticks over the next days.
The chalk sticks dissolve in the weak acids.
Calactin, C29H40O9
Calactin, Pecilocerin B, a cardenolide glycoside, cardiac glycoside, very toxic to vertebrates, in Calotropus procera latex, in Asclepias curassavica
Chebulinic acid, C41H32O27
Chebulinic acid, a gallotannin, may inhibit lipolysis, in Phyllanthus emblica fruit, in Terminalia tebula
38.0 Chemicals standards
ACS, Reagent (American Chemical Society), high quality chemical for laboratory use.
GR, (Guaranteed Reagent), for analytical chemistry, meet or exceeds ACS requirements.
AR, Analytical Reagent, for laboratory and general use, also AR (ACS).
Primary Standard, AR of exceptional purity, for standardizing volumetric solutions and reference standards.
Reagent, highest quality on sale, available on set specifications.
OR, (Organic reagent), for research.
Purified, good quality, no official standard inorganic chemical.
Practical, good quality, no official standards, general applications.
Practical grade organic chemicals may contain isomers of intermediates.
Lab Grade, for histology methods and general applications.
USP, (US Pharmacopoeia).
USP / GenAR (European Pharmacopoeia, PhEur, EP), and British Pharmacopoeia, (BP).
NF, (National Formulary).
The United States Pharmacopoeia and The National Formulary (USPNF), is a book of public pharmacopoeia standards.
It contains standards for (chemical and biological drug substances, dosage forms, compounded preparations), excipients, and dietary supplements.
FCC, (Food Chemical Codex).
CP, (Chemically Pure), general applications.
Technical, general industrial use.
| pH |
Solution A |
Solution B |
pH |
Solution C |
Solution D |
-
|
mL |
mL |
-
|
mL |
mL |
| 10.0 |
25 |
21.8 |
6.0 |
14.6 |
25 |
| 9.6 |
25 |
18.0 |
5.6 |
18.1 |
25 |
| 9.2 |
25 |
13.0 |
5.2 |
21.6 |
25 |
| 8.8 |
25 |
8.0 |
4.8 |
25 |
24.3 |
| 8.4 |
25 |
4.0 |
4.4 |
25 |
19.8 |
| 8.0 |
1.4 |
50 |
4.0 |
25 |
15.7 |
| 7.6 |
3.4 |
50 |
3.6 |
25 |
11.9 |
| 7.2 |
3.8 |
25 |
3.2 |
25 |
8.2 |
| 6.8 |
7.4 |
25 |
2.8 |
25 |
8.2 |
| 6.4 |
11.1 |
25 |
2.4 |
50 |
3.4 |