School Science Lessons
Please send comments to: J.Elfick@uq.edu.au 16 Organic chemistry, tests for organic compounds
Table of contents 220.127.116.11 Acetal 18.104.22.168 Acetates,
(ethanoates) Acetylene 22.214.171.124 Acid
anhydrides 126.96.36.199 Acyl
halides 188.8.131.52.1 Acrylamide 184.108.40.206 Acyclic hydrocarbons 16.1.01 Addition
Alcohols, phenols, thiols 3.8.0 Alcohols,
Fatty alcohols, lauryl alcohol 220.127.116.11a Alcohol,
Ethanol safety 18.104.22.168 Aldehydes 22.214.171.124 Alkaloids from plants 126.96.36.199 Alkanes,
(CnH2n+2), paraffins 188.8.131.52
Alkenes, (CnH2n), olefins 184.108.40.206
Alkynes, (CnH2n-2), acetylenes 220.127.116.11 Amides 18.104.22.168.00
Arenes, benzene 22.214.171.124 Benzoyl
(BPA), Epoxy resin polymer 126.96.36.199a Carbamates 188.8.131.52 Carbides 184.108.40.206 Carboxylic
acids and fatty acids 16.4.1.01 Carbonyls 18.7.23 Chloramines
in swimming pools 220.127.116.11.05
Clenbuterol, C12H18Cl2N2O 16.2.10 Coal tar
products, creosote 18.104.22.168.1 Cyanamides,
inorganic, (CN22-), 22.214.171.124 Cyanocrylates,
"Superglue" 9.10.0 EDTA, ethylenediaminetetraacetic
acid 126.96.36.199 Essential
oils, volatile oils, ethereal oils 16.5.0 Esters,
derivatives of fatty acids 188.8.131.52 Ethane
(C2H6) 184.108.40.206 Ethers,
group: (-O-), in organic compound 220.127.116.11 Ethyl
cellulose 18.104.22.168 Epoxy
resin polymers 22.214.171.124.1 Ethylenediamine 126.96.36.199 Fixed
oils 188.8.131.52 Fluorescent
liquids 16.1.12 Fractional
distillation of crude oil 16.2.2 Halogen compounds,
haloalkanes 1.0 Chlorine compounds 16.14.0 Dioxins,
Agent orange, PCBs 2.0 Iodine compounds 3.0 Bromine compounds 4.0 Fluorine compounds 184.108.40.206 Imides,
imido group: (-CONHCO-) 220.127.116.11a Imines,
imino group: -NH-, or =NH 18.104.22.168 Methane,
CH4 22.214.171.124 Methyl bromide,
bromoethane, CH3Br 126.96.36.199.01
Methylamine ionization reaction 188.8.131.52 Nitrogen compounds,
two or more nitrogen atoms 184.108.40.206.03 Nitrosamines 220.127.116.11.04
Nitramine, (acid-base indicator) 18.104.22.168 Nitriles 22.214.171.124 Nitrites,
(NO2-) 126.96.36.199 Nitroalkanes,
(nitroparaffins) 16.2.4 Nitrogen
compounds, one atom of nitrogen 188.8.131.52 Nitrogen
compounds, 2 or more N atoms 16.1.0 Organic chemistry 16.2.3 Organometal
compounds 16.1.03 Oxidation
reactions, loss of electrons 184.108.40.206 Oximes
(hydrox-imino-alkanes), (C:NOH) 16.2.6 Phosphorous
Physostigmine 3.32.0 Prepare gases,
gas generation apparatus 16.1.00 Prepare
organic compounds 220.127.116.11.02
Prepare phenylamine 18.104.22.168 Quinones 16.1.04 Reduction
reactions, gain of electrons Ribose, C5H10O5 Ribulose,
C5H10O 22.214.171.124 Salts,
organic salts, sodium ethanoate 126.96.36.199 Saturated
hydrocarbons, hexane, C6H14 188.8.131.52 Sulfur compounds 184.108.40.206 Tests
for organic compounds 220.127.116.11 Vegetable
oils, Plant oils, vegetable oils 18.104.22.168 Acyclic hydrocarbons 22.214.171.124 Acyclic hydrocarbons, alkanes, alkenes 126.96.36.199 Alkanes (CnH2n+2),
paraffins 188.8.131.52 Arenes, benzene 184.108.40.206 Butane (C4H10) 220.127.116.11 Cycloalkanes 18.104.22.168 Ethane (C2H6) 22.214.171.124 Hexane (C6H14) 126.96.36.199 Heptane (C7H16) LPG, (Liquefied Petroleum Gas,
LP gas) 188.8.131.52 Methane, CH4 184.108.40.206 Octane (C8H18),
Octane number 220.127.116.11 Octadecan-1-ol, C18H38O 18.104.22.168 Octanol, CH3(CH2)7OH 22.214.171.124 Pentane (C5H12) 126.96.36.199 Propane (C3H8) 188.8.131.52 Alkanes, (CnH2n+2),
Alkanes, cyclohexane, heptane, hexane, liquefied petroleum gas (LPG),
octane, pentane, petroleum spirit
Alkanes: methane, ethane, propane, butane, pentane, hexane, heptane,
octane, nonane. 184.108.40.206 Alkanes (CnH2n+2),
Alkanes, skeletal formula: See diagram 16.1.1 220.127.116.11 Acyclic hydrocarbons, alkanes, alkenes,
alkynes Iodine value 3.29.0 Collect and weigh the gaseous
products of a burning candle 18.104.22.168 Friedel-Crafts reaction 16.2.2 Halogen compounds, haloalkanes,
(alkyl halides), halogen derivatives 22.214.171.124 Nitroalkanes, (nitroparaffins),
(CnH2n+1NO2) 126.96.36.199 Oximes (hydrox-imino-alkanes),
Group: (C:NOH) 188.8.131.52 Petroleum gas, (See
184.108.40.206 to 220.127.116.11) 18.104.22.168 Tests for unsaturated alkanes (Experiments) 22.214.171.124 Alkenes, (CnH2n),
126.96.36.199.0 Alkenes, (CnH2n), olefins 188.8.131.52.1 Prepare ethene, (ethylene), C2H4 184.108.40.206.2 Dienes, isoprene units 220.127.116.11 Alkynes, (CnH2n-2),
18.104.22.168 Alkynes, (CnH2n-2), acetylenes 22.214.171.124.1 Prepare ethyne (acetylene) 126.96.36.199.2 Tests for acetylene 188.8.131.52 Tests for gases from
burning hydrocarbons, oxyacetylene welding 184.108.40.206 Arenes, benzene 220.127.116.11 Arenes, benzene 18.104.22.168.1 Phthalic acid 22.214.171.124 Friedel-Crafts reaction 126.96.36.199 Nitration, (Experiment) 188.8.131.52 Alcohols, phenols,
Alcohols, R-OH, -OH hydroxyl, Prefix: hydroxy-, Suffix: -ol (-OH:
alcohol), (alkanol, alkyl alcohol) 6.6.18 Alcoholic fermentation,
yeast Saccharomyces cerevisiae, (Exp.) 184.108.40.206 Alcohols, phenols, thiols, ethers,
epoxy compounds, acetates (ethanoates), benzoyls, acetals 220.127.116.11.1 Alcohols, primary,
secondary and tertiary aliphatic alcohols 18.104.22.168.1a Tests for alcohols, potassium
manganate (VII) 16.1.3.B Butanol, butyl alcohol,
(C4H9OH) 16.1.3.C Butyl glycol 22.214.171.124.1 Carbolic acid, phenol,
TCP, Dettol 126.96.36.199.3 Cresols 188.8.131.52.1 Dihydric alcohols,
glycol 1.4 List of alcohols 184.108.40.206.2 Naphthols 220.127.116.11.3 Nitroglycerine (UK),
nitroglycerin (USA) 18.104.22.168.4 Nitrocellulose, gun
cotton 12.12.4 Oxidation of glycerol
by potassium permanganate 22.214.171.124 Phenols, group: (OH-C),
in a benzene ring, Phenol = (C6H5O6) 126.96.36.199 Polyhydric alcohols 4.3.8 Prepare alcohol using immobilized
yeast cells, (Exp.) 188.8.131.52.2 Prepare sodium ethoxide 16.1.3.A Propanol, propyl alcohol, (C3H7OH) 184.108.40.206a Pyrogallol 220.127.116.11.4 Resorcinol, (Experiment) 16.1 3.2.5 Triclosan, organohalogens 18.104.22.168.2 Trihydric alcohols, glycerol 22.214.171.124 Thiols, mercaptans, thio alcohols,
Thioalcohols group: (-SH), Suffix: (-thiol), (SH in an organic compound) 16.1.13 Prepare triodomethane,
(iodoform) 16.1.14 Prepare trichloromethane gas, (chloroform) 126.96.36.199 Reaction of acetone with bleaching
powder 188.8.131.52 Reaction of ethyl alcohol with
bleaching powder 184.108.40.206 Carbides 220.127.116.11 Carbides Methanides,
aluminium carbide, Al4C3 Acetylides,
calcium carbide CaC2 Sesquicarbides,
e.g. Mg2C3 Covalent carbides,
boron carbide, carborundum Silicon carbides
(Carborundum) 16.1.12 Fractional distillation
of crude oil Asphalt
16.1.12 Fractional distillation of crude oil 18.104.22.168 Petroleum gas, (methane, ethane,
propane, butane), LPG 22.214.171.124 Naphtha, (ligroin), processed to
make gasoline 126.96.36.199 Petrol, "gas", gasoline, motor
fuel 188.8.131.52 Kerosene, kerosine, paraffin oil,
jet engine fuel, tractor fuel 184.108.40.206 Diesel oil, gas oil or diesel distillate,
diesel fuel, heating oil 220.127.116.11 Lubricating oil, motor oil, grease 18.104.22.168 Paraffin wax, heavy gas, fuel oil 22.214.171.124 Residuals, bitumen, "tar", asphalt,
waxes, petroleum jelly 126.96.36.199 Nitrogen compounds,
two or more nitrogen atoms 188.8.131.52 Azide compounds 184.108.40.206 Azo compounds 220.127.116.11 Diazo compounds 18.104.22.168 Phenylhydrozone compounds 22.214.171.124 Sulfur compounds
Sulfur compounds, (For the "thio" prefix, replace oxygen by sulfur,
e.g. thiobenzamide [PhC(=S)NH2]) 126.96.36.199 Isothiocyanates, (old name: mustard
oil), (RN=C=S), Mustards: [X(CH2.CH2)2S] 188.8.131.52 Sulfides Sulfonic acids,
group: R-SO2OH, e.g. methanesulfonic acid, CH3SO2OH,
Salts or esters: sulfonates 184.108.40.206 Sulfonium compounds 220.127.116.11 Thiocyanates: [RC(=O)SN], Salts
and esters of thiocyanic acid, HSCN, e.g. methyl thiocyanate (CH3SCN) 18.104.22.168 Silicones: polymeric
unbranched siloxanes, formula (-OSiR2-)n (R not
equal to H) 22.214.171.124 Siloxanes 126.96.36.199 Sulfoxide 188.8.131.52 Thiols (mercaptans) 184.108.40.206.2 Allyl mercaptan 220.127.116.11.1 Methyl mercaptan 18.104.22.168.3 Ethyl mercaptan, ethanethiol,
CH3CH2SH 22.214.171.124.4 Thiophene, thiolane, THT, (CH2)4S 16.1.0 Organic chemistry,
Carbon, C See diagram 16.0.0: Organic chemistry
functional groups See diagram 16.0.1: Tetrahedral geometry
of carbon, methane molecule, isobutyl alcohol
Organic chemistry is the chemistry of carbon compounds.
Hydrocarbons contain carbon and hydrogen only.
The main types are the alkanes, alkenes and alkynes. In alkenes and
alkynes, addition reactions occur at the double bonds =
or triple bonds. Be careful! When heating organic chemicals, do not point the test-tube
Organic compounds may suddenly vaporize and spurt out of the test-tube!
1. Classification by molecular framework
1.1 Acyclic compounds have chains of unbranched or branched carbon
1.2 Carbocyclic compounds have rings of carbon atoms
1.3 Heterocyclic compounds have rings of carbon atoms with one atom
in a ring not carbon, e.g. O, N, S
2. Classification by functional group, e.g. hydroxyl group, OH, is
characteristic of alcohols 16.1.00 Prepare organic compounds 16.1.01 Addition reactions 16.1.02 Substitution reactions, (displacement
reactions) 16.1.03 Oxidation reactions, loss of electrons 16.1.04 Reduction reactions, gain of electrons 126.96.36.199 Methane Methane, CH4,
natural gas 188.8.131.52 Methane, CH4 184.108.40.206 Methane with chlorine, (dangerous) 3.39.1 Methane with steam, (Experiment) 220.127.116.11 Prepare methane gas, (Experiment) 18.104.22.168 Reduce copper oxide with natural
gas, methane, (Experiment) 22.214.171.124 Tests for methane gas, burn methane
(Experiments) 16.1.01 Addition reactions
Atoms are added to the two atoms of a double bond or triple bond in
an unsaturated compound, also when no atoms are replaced.
but extra covalent bonds are formed.
Alkenes (olefins) or alkynes (acetylenes) --> haloalkanes (alkyl
halides), or primary alkanols (alcohols), or secondary alkanols (alcohols)
Example: HCl + CH2CH2 --> CH3CH2Cl 16.1.02 Substitution reactions,
Replacement of an atom or group in a molecule by another atom or group
Alkanes (paraffins) --> haloalkanes (alkyl halides) --> amines
Haloalkanes (alkyl halides) <--> primary alkanols (alcohols),
Alkanoic acids --> esters --> amides
Example: CH4 + Cl2 --> CH3Cl +
HCl [chlorination produces chloromethane (methyl chloride) and HCl.] 16.1.03 Oxidation reactions,
loss of electrons
Primary alcohols can be directly oxidized to aldehydes or carboxylic
Primary alkanols (alcohols), (-CH2-OH) --> alkanals
Example: CH3OH + O2 --> CH2O +
H2 (Pt catalyst) [Oxidation of methanol to methanal using a
Alkanals --> alkanoic acids, e.g. butanoic acid, CH3(CH2)2COOH
Secondary alkanols (alcohols), (CH3)2CHOH -->
alkanones 16.1.04 Reduction reactions,
gain of electrons
Alkanals (aliphatic aldehydes) --> primary alkanols (alcohols),
Add drops of formalin to a test-tube one quarter filled with Fehling's
A and B solutions and heat to boiling.
Note the yellow then orange then red precipitate of copper (I) oxide.
The copper from the copper (II) sulfate solution has been reduced
from copper (II) to copper (I). 126.96.36.199 Acyclic hydrocarbons,
alkanes, alkenes, alkynes
|See diagram 16.1.1: Alkanes, alkenes,
| See 10.6.3: Distil crude oil and
collect the fractions
Alkanes, alkenes, alkynes or their derivatives are aliphatic compounds,
i.e. non-cyclic organic compounds.
Acyclic molecules have carbon atoms in chains but not in rings.
The chains may be unbranched or branched.
Aromatic compounds contain a benzene ring in the molecule.
Hydrocarbon compounds contain only hydrogen and carbon.
Hydrocarbons are usually colourless and have low solubility in water.
Crude oil is a mixture of hydrocarbons.
Hydrocarbons may be saturated, i.e. have only single bonds, or unsaturated,
i.e. contain multiple bonds, e.g. double bond =, triple bond . Iodine value is the number of grams of iodine
absorbed by 100 g of fat or oil, to indicate the amount of unsaturated
acids. 188.8.131.52 Alkanes (CnH2n+2),
The first 10 unbranched alkanes and molecular formula: methane (CH4),
ethane (C2H6), propane (CH3H8),
pentane (CH5H12), hexane (CH6H14),
heptane (CH7H16), octane (CH8H18),
nonane (CH9H20), decane (CH10H22).
Alkanes burn in oxygen to give carbon dioxide and water.
Candle wax is a mixture of different alkanes that are solid at room
Alkanes are usually associated with natural petroleum deposits and
can be distilled from petroleum.
1. Alkanes (paraffins) are saturated hydrocarbons, i.e. all single
bonds between C atoms, have formula CnH2n+2
and names end in "ane".
The names of unbranched alkanes come from the number of carbon atoms.
The name of branched alkanes come from the longest chain of carbon
The hydrocarbon branches, alkyl groups, symbol R, are formed by removing
one hydrogen atom from the alkane and named by
changing the "ane" to "yl", e.g. methane, CH4 to methyl,
CH3-, also "Me".
The carbon atoms of the longest continuous name are numbered starting
at the end of the chain closest to the first branch, e.g. an
eight carbon chain with an ethyl group attached to carbon 5 and a
methyl group attached to carbon 3 and carbon 4 is called
Saturated hydrocarbons, e.g. hexane, C6H14,
all carbons have either four or three hydrogens bonded to them and no
triple bonds or rings, react in almost the same way. 2. Formation of alkanes
2.1 Hydrogenation of alkenes --> alkanes
CH2=CH2 + H2 --> CH3-CH3
ethylene + hydrogen --> ethane
CH3CH=CHCH3 + H2 --> CH3CH2CH2CH3
2.2 Decarboxylation (remove CO2) from molecules that have
- COOH group.
RCOONa + NaOH --> R-H + Na2CO3 (dry distillation
with soda lime)
CH3COONa + NaOH --> CH4 + Na2CO3 184.108.40.206 Cycloalkanes
Cycloalkanes, CnH2n, cyclanes, polymethylenes,
cycloparaffins, saturated carbon rings.
Cycloalkanes are saturated hydrocarbons with a ring of carbon atoms,
e.g. cyclopropane, C3H6, the simplest cyclobutane,
cyclohexane, cycloheptane, cyclooctane.
The position of branches depends on the alphabetical order of the
branch names so that highest in order is attached to carbon 1,
Cyclopropane, C3H6, colourless gas, anaesthetic
Permethrin, C21H20Cl2O3 220.127.116.11 Arenes, benzene See 18.104.22.168: Aromatics, aromatic
compounds, benzene derivatives, arenes See diagram 16.8.1: Benzene compounds Benzene, C6H6,
has a stable six-sided ring structure.
Arenes, e.g. benzene, naphthalene, anthracene, phenanthrene.
Arenes do not mix with water, but they do mix with hydrocarbons and
all non-polar solvents.
Arenes usually burn with a smoky flame, as do most aromatic compounds,
because of the high carbon: nitrogen ratio.
So when they burn in air, some carbon soot usually remains in the
Arenes are called aromatic compounds because the first arenes were
isolated from fragrant oils.
However, nowadays aromatic refers to the structure not the smell.
22.214.171.124.1 Phthalic acid
Phthalic acid, C8H6O4, benzene-1,2-dicarboxylic
acid, formerly derived from naphthalene.
Phthalic anhydride, benzene-1,2-dicarboxylic anhydride, phthalandione,
Toxic. strong skin irritant
Phthalic anhydride, C8H4O3, used
to produce phthalic esters, widely used as a chemical plasticiser, producing
plastics from vinyl
chloride. 3.0.4 Phthalates 126.96.36.199 Nitration See 10.01.10: Liebig condenser
The reaction substitutes a hydrogen atom in an arene ring by a -NO2
Heat benzene with a mixture of nitric and sulfuric acid catalyst in
a Liebig condenser at 330 K.
benzene + HNO3 --> benzene-NO2 + H2O
benzene + NO2+ --> benzene-NO2
Also, some 1.3-dinitrobenzene may form. 188.8.131.52 Friedel-Crafts
The reaction substitutes a hydrogen atom in an arene ring of a halogenalkane
by an organic group, R, using aluminium chloride catalyst.
RCl + AlCl3 --> R+ + AlCl4-
For example, benzene with chloromethane forms methyl benzene.
benzene + CH3+ --> benzene-CH3
CH3Cl +AlCl3 --> CH3+
+ AlCl4- 184.108.40.206 Tests for unsaturated
1. Ignition tests for unsaturation
Ignite a substance in an evaporating basin and observe the smoke over
The darker or more sooty the smoke, the more unsaturated, e.g. aromatic
If clear over a luminous flame the compound is saturated, e.g. n-hexane.
2. Bromine tests for unsaturation.
Bromine is a coloured compound but it reacts with with double bonds
or triple bonds to form a colourless brominated compound.
alkene or alkyne + bromine water, yellowish colour disappears.
3. Decolorization of bromine water.
Hexane does not decolorize bromine water.
Aromatic compounds also do not decolorize bromine water because they
are stable compounds.
4. Baeyer test
Change in colour of the reagent (purple permanganate to brown manganese
dioxide), redox reaction
Brominate hexane and other saturated hydrocarbons with the right wavelength
of light and shining it on the reaction vessel, or adding
peroxide or by heating the reaction. 220.127.116.11 Methane, CH4 See diagram 16.0.1: Tetrahedral geometry
of carbon, methane molecule, isobutyl alcohol
Methane is the simplest alkane.
It is colourless and odourless and found in natural gas and bubbles
of methane in swamp water.
Fire damp, which causes explosions in coal mines, is a mixture of
methane and air.
Methane is found in large quantities usually associated with petroleum.
It has largely displaced town gas produced from coal.
Methanogenic bacteria live in swamps and in the human gastrointestinal
tract where they liberate methane causing flatulence.
After carbon dioxide, methane produced by bacteria in rice paddies
may be the second most important greenhouse gas made by man.
They produce methane gas anaerobically (without oxygen) by removing
the electrons from hydrogen gas.
The electrons and H+ ions from hydrogen gas are used to
reduce carbon dioxide to methane.
H+ ions combine with the oxygen from carbon dioxide to
form water and electrons move through the steps of an anaerobic electron
transport system to the phosphorylate of ADP to form ATP.
Methane is a simple asphyxiant. 18.104.22.168 Prepare methane
gas, (Experiment) See diagram 3.32: Collect insoluble gases
1. Mix 1 part sodium acetate with 3 parts soda lime.
Heat in a dry pyrex test tube or flask.
Collect the gas over water.
2. Heat 20 g of sodium acetate-3-water in a Pyrex test-tube until
the salt becomes anhydrous.
Grind the cooled salt with an equal amount of soda lime [NaOH + Ca(OH)2]
granules in a mortar and pestle.
Mix thoroughly and place the mixture in a Pyrex test-tube.
Heat the test-tube and collect the gas over water. Be careful! Pull out the delivery tube before heating the water
stops so that water will not be "sucked back" into the
hot test-tube! For safety, wrap the test-tube in wire gauze.
CH3COONa + NaOH --> CH4 + Na2CO3
sodium acetate + sodium hydroxide --> methane + sodium carbonate 22.214.171.124 Tests for methane
gas, burn methane, (Experiment)
Light the gas in the test-tube with a glowing splint.
The gas burns with a clear flame.
CH4 + 2O2 --> CO2 + 2H2O
Repeat the experiment using glacial acetic acid soaked in glass wool
+ soda lime. 126.96.36.199 Methane with chlorine,
When a mixture of an alkane and chlorine gas are stored at low temperature
in the dark no reaction occurs.
At high temperatures or in sunlight, a substitution exothermic reaction
called chlorination occurs to produce chloromethane, methyl
chloride and HCl.
CH4 + Cl2 --> CH3Cl + HCl
Excess chlorine can produce dichloromethane (methylene chloride) trichloromethane
(chloroform) and tetrachloromethane (carbon
A mixture of chlorine and methane explodes violently in direct sunlight
forming hydrogen chloride and free carbon.
BE CAREFUL! Do not mix chlorine and methane!
CH4 (g) + 2Cl2 (g) --> C (s) + 4HCl (g) +
energy 188.8.131.52 Reduce copper oxide
with natural gas, methane, (Experiment)
1. Pass natural gas, about 95% methane, over heated copper (II) oxide
The reduction reaction is slow and may need twenty minutes of strong
The copper does not glow with heating so it is not clear when all
the copper oxide has been reduced.
4CuO (s) + CH4 (g) --> 4Cu (s) + 2H2O (l)
+ CO2 (g)
2. Repeat the experiment with a 1 cm cubic piece of metaldehyde in
the reduction tube.
The reduction is quicker.
3. Repeat the experiment with natural gas that has bubbled through
The reduction is quicker and a slight glow is seen as the copper oxide
6CuO (s) + C2H5OH (l) --> 6Cu (s) + 3H2O
(l) + 2CO2 (g) 184.108.40.206 Ethane (C2H6)
| See 3.32.0: Prepare gases with
a gas generation apparatus, Collect insoluble gases over water.
| See diagram 16.1.1: Ethane
Ethane is a colourless and odourless gas, which has properties similar
(This experiment was called the "wet asbestos method" because asbestos
wool, now not allowed in schools, was used to soak up the
methyl iodide in the test-tube.)
Pour 2 cm methyl iodide in a test-tube.
Add 5 g of copper turnings and push it down firmly with a spatula.
Set up the apparatus and heat the mixture.
2CH3I + 2Cu --> C2H6 + Cu2I2 220.127.116.11 Propane (C3H8)
Colourless liquefied petroleum gas, a bottled gas, b.p. -42.2oC,
catalytic cracking forms propylene, propellant, aerator, fuel for gas
barbecue and blow torch 18.104.22.168 LPG (Liquefied
Petroleum Gas, LP gas)
LPG is a clean burning fuel and is stored in gas cylinders as bottled
LPG is a simple asphyxiant.
It consists of propane (about 95%) together with varying proportions
of butane, propylene and butylene.
A bad smelling compound is added so that the presence of the gas can
be easily detected.
Incomplete combustion forms carbon monoxide.
Do not search for a gas leak with a lighted match or lighted taper.
Use a soap solution. 22.214.171.124 Butane (C4H10)
| See diagram 3.32: Collect insoluble gases
over water, See 3.
| See diagram 16.1.1: Butane formula
Butane, b.p. -0.5oC, relative density 0.60 at 0oC,
is stored as liquid under pressure in steel cylinders giving Calor gas
Cigarette lighter fuel is 90% butane, isomer isobutane.
(This experiment was called the "wet asbestos method" because asbestos
wool, now not allowed in schools, was used to soak up the
ethyl iodide in the test-tube.)
Pour 2 cm ethyl iodide in a test-tube.
Add 5 g of copper turnings and push it down firmly with a spatula.
Set up the gas generation apparatus and heat the mixture.
2C2H5I + 2Cu --> C4H10
+ Cu2I2Combustion of butane
Butane / Oxygen combustion
2C4H10 + 13O2 --> 8CO2
+ 10H2O + energy 126.96.36.199 Pentane (C5H12)
Pentane, b.p. 36.3oC, relative density 0.63, is made by
distillation of petroleum. 188.8.131.52 Hexane (C6H14)
Hexane, b.p. 68.7oC, relative density 0.66, exists as five
compounds with same formula, normal hexane, n-hexane, in petrol and petroleum
ether solvent, colourless liquid ethereal odour.
"Shellite" (Australia) is 60% hexane and 40% heptane. 184.108.40.206 Heptane (C7H16)
Heptane, b.p. 98oC, relative density 0.68, nine isomers,
normal heptane has similar properties to normal hexane. 220.127.116.11 Octane (C8H18),
Octane number See diagram 16.1.1h: Octane ratings
Octane, b.p. 126oC, relative density 0.702 at 20oC,
exists as eighteen compounds, in petroleum.
Isomeric with iso-octane, 2, 2, 4-trimethylpentane (CH3)3CCH2CH(CH3)2.
Octane number See: 18.104.22.168: Spark plugs, pre-ignition
Some hydrocarbons with unbranched carbon chains prematurely explode
in the cylinder and produce an audible knocking sound or
"ping" sound (knocking, pinking).
A scale of "knock property" has isooctane (2, 2, 4-trimethylpentane)
at 100 (a good fuel) and heptane at 0 (a poor fuel).
So gasoline with octane number 80 has the same properties as a mixture
of 80% isooctane and 29% heptane.
Octane number is the percentage of iso-octane normal heptane mix with
the same knocking behaviour of the fuel being tested, so it
indicates the knock rating of a motor fuel.
A high octane fuel has a longer self-ignition delay in motor car engine.
In Brisbane, most " family cars" use 91 octane "unleaded petrol".
This is the lowest octane rating of the different petrol sold in garages.
A high octane rating of a fuel means that it has less tendency to
pre-ignite in a high compression engine.
Pre ignition means that, before the spark plug has fired, the fuel
air mixture burns because of the heat created in the cylinder by
Unleaded petrol has the octane rating 98.
Engine compression ratio
Octane number to be knock-free
Octadecan-1-ol, C18H38O, octadecyl alcohol,
1-octadecanol, stearyl alcohol
Use octadecan-1-ol for melting point curve experiments. 22.214.171.124, Octanol, CH3(CH2)7OH
Octanol, CH3(CH2)7OH, 1-octanol,
octyl alcohol, n-octyl alcohol, octan-1-ol, caprylic alcohol, Flammable 3.10.0 Poisons and First Aid: See
Octanol 126.96.36.199 Alkenes (CnH2n),
Alkene, R1R2C=CR3R4, (double
CC bond =), Prefix: alkenyl-, Suffix: -ene (no principal functional group)
Alkene, (olefins, olefines), CnH2n, e.g. ethylene,
ethene (ethylene), (H2C=CH2), amylene, propadiene
(allene), (R2C=C=CR2), dienes buta-1. 2-diene
(CH3CH=C=CH2), amylene See diagram 16.1.1: Cyclodienes, cis-trans
1. Suffix: -ene for C=C (olefin, olefins, olefines) are unsaturated
hydrocarbons with at least one double bond between C atoms, C=C.
Alkenes have the formula CnH2n.
Alkenes include ethene (ethylene, C2H4, CH2=CH2),
ethenyl (vinyl CH2=CH-), 3-propenyl (allyl, CH2=CH-CH2-),
e.g. vinyl chloride
(chlorethene, CH2CHCl), allyl chloride (3-chloropropene
(In the textile trade "olefin" refers to synthetic fibre, polyolefin
fibre, that are long-chain polymers of ethylene or propylene,
i.e. polyethylene (polypropylene, PP).
Alkenes decolorize acidified potassium permanganate solution and bromine
2. The cycloalkenes, cycloolefins, are closed chain, non-aromatic
forms, e.g. cyclopropene, CH.CH.CH2, cyclobutene, cyclopentene,
cyclohexene. 188.8.131.52.1 Prepare ethene
(ethylene), C2H4 See 3.32.0: Prepare gases with a
gas generation apparatus
The preparation is an example of the dehydration of an alcohol.
1. Slowly add 10 mL of concentrated sulfuric acid to 5 mL of ethanol
and 1 g of powdered aluminium sulfate in the gas preparation
apparatus. Be careful! Pass the gas formed through sodium hydroxide solution
to remove sulfur dioxide and carbon dioxide.
Collect the gas over water.
Heat only if necessary. Pass through sulfuric acid as dehydrating
CH3CH2OH --> H2C=CH2 +
H2O 2. Add 3 mL ethanol to a plug of glass wool in
a boiling tube.
Cover the glass wool with porous pot and heat the porous pot.
C2H5OH --> C2H4 (g)
+ H2O 3. Prepare ethene (ethylene) with ethanol, breakdown
of ethanol to ethene (ethylene, H2C=CH2). See 3.96: Breakdown ethanol to ethene
Ethene (ethylene, H2C=CH2), gas is a plant growth
It is produced in wounded, diseased and ripening tissues where it
reacts with auxins to induce fruit ripening and abscission of leaves
It is used to ripen stored fruit artificially, e.g. bananas.
Put some cleaned and dried unglazed porcelain chips in a flask.
Add 10 mL of pure ethanol (absolute alcohol).
Slowly pour 30 mL of concentrated sulfuric acid down the sides of
the flask. Be careful! Shake the flask gently under cool water to avoid alcohol being
carbonized because of increase in temperature.
Fit the flask with a thermometer and a delivery tube inserted in a
two-holes rubber stopper.
Heat the flask to raise the temperature quickly to 170oC,
then control at 170oC.
This heating procedure is used to increase the use ratio of ethanol
and decrease by-products.
Wait until exclusion of the air in the flask and then collect the
produced ethene gas over water.
Concentrated sulfuric acid and sodium hydroxide solution can be used
to absorb and remove the small quantities of the ethyl ether
(sulfuric ether) vapour, carbon dioxide and sulfur dioxide present
in the produced ethene.
C2H5OH (l) -> C2H4
(g) + H2O at 170oC. 4. Prepare ethene (ethylene), with ethanol, alternative
method See diagram 16.10.3: Prepare ethene
Absorb ethanol in cotton wool and push this to the bottom of a hard
Pack small pieces of unglazed porcelain in the middle of the test-tube.
Fit a delivery tube to collect ethene gas over water.
First heat the porous pot strongly and then heat gently the cotton
wool to produce some ethanol vapour.
This vapour breaks down over the hot porous pot to produce ethene
gas and water vapour.
The temperature should be above 170oC otherwise the reaction
produces dimethyl ether.
Collect the ethene over water.
Be careful! Disconnect the delivery tube when heating stops to avoid
a suck back of water onto the hot porous pot. 184.108.40.206.2 Dienes, isoprene
units See diagram 220.127.116.11.2: Isoprene
1. Dienes are alkenes with two double bonds in the molecule.
2. Cumulated dienes have double bonds next to each other.
3. Conjugated dienes have 2 double bonds separated by a single bond:
Isoprene, 2-methyl-1.3-butadiene, CH2:C(CH3)CH:CH2
4. Cyclodienes, 1.3-cyclohexadiene, 1.4-cyclohexadiene
5. The 5-carbon isoprene units in natural products have a four carbon
chain and a one carbon branch at C2, i.e. [C(CC)CC]
Terpenes have linked isoprene units as in natural rubber.
Rosin is a solid amber residue made by the distillation of turpentine
using pine stumps.
Natural turpentine contains the terpene called pinene, C10H16. 18.104.22.168 Alkynes (CnH2n-2),
Alkyne, R1-CC-R2, (triple CC bond involves 6 electrons, e.g. acetylene,
Alkyne, Prefix: alkynl-, Suffix: -yne (no principal functional group),
1. acetylenes: ethyne (acetylene), (C2H2 (HCCH),
Suffix: (-yne), for (CC), (acetylenes), are unsaturated hydrocarbons
with at least one triple bond (), between C atoms, include ethyne
(C2H2), acetylene, (HCCH), 3-propargyl (propargyl),
Alkynes decolorize acidified potassium permanganate solution and bromine
2. The cycloalkynes, are closed chain, non-aromatic forms, e.g. cyclooctyne,
C8H12 (the smallest form). Acetylene
C2H2, ethyne, Use acetylene in a fume cupboard
or ruse very small quantities in a well-ventilated area.
Use eye and skin protection to avoid splashes.
Mixtures of acetylene and air may be dangerously explosive. Also,
explosive acetylides form when acetylene reacts with silver or
copper (I) salts.
Formerly, bicycle "carbide lamps" used calcium carbide + water -->
acetylene + calcium hydroxide.
However, the calcium carbide used to decompose in moist air to form
the unpleasant odour of acetylene.
The gas has a foul smell because of the presence of traces of phosphorus
This decomposition could be lessened by pouring petroleum over the
calcium carbide to exclude air and moisture.
Acetylene forms highly explosive mixtures with air, but is otherwise
As prepared from the reaction of calcium carbide with water, it usually
has an evil smell because of the presence of small amounts of
Do not inhale the impure gas. Handle acetylene cylinders with care.
Unplanned release of a large quantity of acetylene may result in a
serious fire or explosion.
In acetylene cylinders, acetylene is dissolved in acetone supported
on a porous diatomaceous earth base.
The pressure inside an acetylene cylinder is therefore lower than
in other cylinders that contain compressed gases, e.g. nitrogen. 22.214.171.124.1 Prepare ethyne
(acetylene) See diagram 16.1.5: Prepare ethyne
The main hazard with calcium carbide is the ignition of air / acetylene
A violent explosion may occur, depending on the proportions of air
Acetylene, when undiluted with air, burns with a smoky flame.
Before igniting acetylene, be sure that it is not mixed with air.
Commercial calcium carbide usually contains sulfur and phosphorus
compounds that react with water to form strongly smelling
gaseous impurities that act as a convenient indicator for the presence
1. In a fume cupboard, put a 2 g lump of calcium carbide in a 250
Add water drop-by-drop.
Calcium carbide reacts vigorously with water forming acetylene gas
(ethyne) and releasing a considerable amount of heat.
Ignite the resulting bubbles of acetylene.
2. On a metal tray or shallow container in a fume cupboard, add water
drop-by-drop to one lump of calcium carbide.
The water will hiss and the gas will be produced.
The lump will fall to pieces to form a powder of calcium hydroxide.
Do not attempt to ignite the acetylene produced.
3. Put a < 5 g lump of solid calcium carbide in 500 mL of water
and ignite the ethyne produced.
Do this experiment outside, with the observers at least 2 metres away.
4. Formerly, bicycle "carbide lamps" used the following reaction.
Put sand in a dry test-tube and add pieces or lumps (not powder) of
calcium dicarbide (calcium carbide).
Add water drop by drop.
Collect the gas over water.
CaC2 + 2H2O -> C2H2 +
calcium dicarbide + water -> ethyne (acetylene) + calcium hydroxide
5. Collect acetylene from oxy-acetylene equipment
126.96.36.199.2 Tests for acetylene
Light the gas in the test-tube with a glowing splint.
The gas burns with a smoky flame. 188.8.131.52 Alcohols, phenols,
thiols, ethers, epoxy compounds, acetates (ethanoates) benzoyls, acetals See diagram 16.0.1: Tetrahedral geometry
of carbon, methane molecule, isobutyl alcohol
Alcohols (ROH), (-ol), alkanols, e.g. methanol (methyl alcohol), (CH3OH),
ethanol (ethyl alcohol), (C2H5OH)
Alcohols are organic compounds with the functional group -OH, but
when attached to an aromatic ring called phenols.
Alcohols, alcohols group: (-OH) Suffix: (ol) primary, secondary and
tertiary aliphatic alcohols, e.g. Primary alcohol, methanol, CH3OH,
Secondary alcohol, propan-2-ol, (CH3)2CHOH,
Tertiary alcohol, 2-methylpropan-2-ol, (CH3)3COH.
Alcohols, R-OH, are compounds in which a functional group, the hydroxyl
group, -OH, is attached to a saturated carbon atom,
The "hydroxyl" refers to the radical HO-.
The "alcohol" in alcoholic beverages is ethanol, ethyl alcohol, CH3CH2OH. 184.108.40.206a Ethanol safety
Do not heat ethanol over an open flame but use a water bath.
However, ethanol may be use in small quantities in alcohol burners
to measure heat of combustion and for reaction with alkanoic acids
to form esters.
Ethanol forms violently explosive mixtures with nitric acid and other
Ethanol with acidified dichromate solutions is highly exothermic.
Ethanol reacts violently with potassium.
Alcohol flammability, ethanol > 70% (PG II), < 70% (e.g. 24%)
(PG III), < 24% not clasified as "dangerous goods" 16.1.3.A Propanol (C3H7OH)
1. Propan-1-ol, 1-propanol
(n-propyl alcohol), (CH3CH2CH2OH),
Highly flammable, Toxic if ingested
2. Propan-2-ol, 2-propanol
(iso-propyl alcohol), (CH3CH(OH)CH3), C3H7OH,
sec-propyl alcohol, rubbing alcohol, Flammable
Potassium dichromate as an oxidizing agent, propan-2-ol (isopropanol)
--> propanone (acetone) + water: 15.2.3,
(See: 5.) 16.1.3.B Butanol, butyl
alcohol (C4H9OH) has 4 isomers:
("Butanol" may refer to either butan-1-ol or butan-2-ol.)
1. Butan-1-ol, n-butanol, 1-butanol, n-butyl alcohol, butyl alcohol,
(primary alcohol), CH3(CH2)3OH, (C4H9OH),
(biobutanol), product of carbohydrate fermentation, common flavorant
2. Butan-2-ol, sec-butanol, 2-butanol, sec-butyl alcohol, (secondary
alcohol) CH3CH(OH)C2H5, (C4H9OH),
secondary butyl alcohol, s-butyl alcohol, product of grain and hops
3. isobutanol, isobutyl alcohol, IBA, (CH3)2CHCH2OH,
(C4H9OH), 2-methylpropan-1-ol, 2-methyl-1-propanol,
additive to reduce
viscosity, flavouring agent
4. tert-butanol, t-butanol, tert-butyl alcohol, (CH3)3COH,
(simplest tertiary alcohol, so is often just called "butyl alcohol"
or "butanol", with the hydroxyl on the same carbon with three methyl
groups.), paint remover, solvent, Harmful by all routes, flammable 16.1.3.C Butyl glycol
2-butoxyethanol, butyl cellosolve, C4H9OCH2CH2OH,
butyl ether of ethylene glycol, pH 11. in window cleaner "Windex", inks,
solvents 220.127.116.11.1 Dihydric alcohols,
The dihydric alcohols, glycols, diols, have two hydroxyl groups on
different carbon atoms, e.g. 1. Ethane-1.2-diol, ethylene
ethanediol, glycol,1.2-dihydroxyethane, (HOCH2CH2OH),
(CH2OH.CH2OH), b.p. 197.5oC, car radiator
antifreeze, paint and
2. Butane-1.4-diol [HO(CH2]4OH]
CH2CH2 (oxidation) --> CH2OCH2
(+ water) --> HOCH2CH2OH
ethene (oxidation) --> epoxyethane (+ water) --> ethane-1.2-diol
(glycol, antifreeze) 18.104.22.168.2 Trihydric alcohols,
The trihydric alcohols, have three hydroxyl groups on different carbon
atoms, e.g. 1.2,3-trihydoxypropane, glycerol
[HOCH2CH(OH)CH2OH] 22.214.171.124.3 Nitroglycerine
(UK), Nitroglycerin (USA)
glycerol + cold mixture of concentrated sulfuric acid + nitric acid
ester of nitric acid
Nitroglycerine is a colourless, insoluble oil, solidifies on cooling,
contact explosive, used to make dynamite, cordite.
Nitroglycerine is a very unstable liquid that explodes if given a
It freezes at 13oC but is more likely to explode if solid.
It is used to make safer explosives, e.g. dynamite.
It is also used in very small tablets for the heart condition angina
pectoris where people get out of breath and suffer pain in the chest
from over-exertion. 126.96.36.199.4 Nitrocellulose,
This preparation is too dangerous to be done in schools.
Potassium nitrate is dissolved in concentrated sulfuric acid to produce
a dangerous vapour, then cooled in an ice and salt mixture, then
cotton balls are added.
Later more sulfuric acid is added, then the cotton balls are removed
and placed in sodium bicarbonate solution until no more bubbles
form, then dried. 188.8.131.52.1 Alcohols, primary,
secondary and tertiary aliphatic alcohols
Primary alcohols RCH2OH, Secondary alcohols R2CHOH,
Tertiary alcohols R3COH See 3.38: Carbon dioxide and fermentation
for brewing See 16.5.10: Rubbing alcohol,
surgical spirit 184.108.40.206.1a Tests for alcohols, potassium
manganate (VII) Primary alcohols
Primary alcohols, e.g. methanol (methyl alcohol, CH3OH),
propanol (isomer propan-1-ol, n-propyl alcohol, CH3CH2CH2OH),
and butan-1-ol (1-butanol, n-butanol, CH3(CH2)3OH),
have two hydrogen atoms attached to the carbon atom attached to the
hydroxyl group (-OH).
So they all have -CH2OH in their molecules.
They can be directly oxidized to aldehydes or carboxylic acids using
(O)R1-CH(OH)-R2 --> R1-C(O)-R2(O)R-CH2OH
--> R-CHO(O)R-CHO --> R-COOH
1.1 Allyl alcohol, CH2:CHCH2OH, prop-2-en-1-ol,
2-propen-1-ol, Highly toxic by all routes
Secondary alcohols, e.g. propan-2-ol (CH3)2CHOH,
rubbing alcohol, isopropyl alcohol and secondary butyl alcohol, butan-2-ol
(CH3CH2CH[CH3]OH), [ or CH3CH(OH)C2H5],
have one hydrogen atom attached to the carbon atom attached to the hydroxyl
So they all have (-CHOH), in their molecules.
They can be slowly oxidized to ketones.
(O)R1-CH(OH)-R2 --> R1-C(O)-R2 Isopropanol,
isopropyl alcohol Tertiary alcohols
Tertiary alcohols, e.g. 2-methylpropan-2-ol, 2-methyl-2-propanol (CH3)3COH,
tertiary butyl alcohol has no hydrogen atom
attached to the carbon atom attached to the -OH group.
So they all have -COH in their molecules.
220.127.116.11.1a Tests for
alcohols, potassium manganate (VII)
Tests for primary, secondary and tertiary aliphatic alcohols
To one drop of each alcohol in three test-tubes, add saturated potassium
manganate (VII) solution drop by drop with shaking.
If decolorization occurs, continue adding drops until pink coloration
persists, as shown by spot testing on filter paper.
Add one drop of concentrated sulfuric acid and resume adding potassium
manganate (VII) drop by drop.
No decolorization occurs with tertiary alcohols.
The colour eventually fades with secondary alcohols, but persists
with primary alcohols. 18.104.22.168.2 Prepare sodium
Sodium ethoxide is the salt of a weak acid, ethanoic acid, and a strong
base, sodium hydroxide.
Add a pinhead size piece of sodium to 1 mL of ethyl alcohol.
Tests for hydrogen gas:
Na (s) + 2C2H5OH (l) --> 2C2H5ONa
(s) + H2 (g)
sodium + ethanol --> sodium ethoxide + hydrogen
Evaporate the sodium ethoxide solution to form white crystals.
Add drops of water and tests for litmus that turns blue. 22.214.171.124 Phenols
| See diagram 126.96.36.199: Phenols, quinones,
naphthols, coniferyl alcohol (p-coumaryl alcohol), urushiol, organohalogens
| See diagram 188.8.131.52: Phenols, quinones
| 184.108.40.206: Antioxidant phenols,
antioxidants, vitamin E, beta carotene
| 220.127.116.11.0: Cholesterol, C27H46O
1. Phenols, Ar-OH, are compounds with an hydroxyl group, -OH, firmly
attached to an aromatic ring, e.g. benzene, 2-naphthol,
Phenols (hydroxyl group -OH), connected to a carbon atom in a benzene
ring, benzene-OH, hydroxybenzenes
The -OH is so firmly attached that the O-H bond tends to break to
lose an H+ ion to form a weak acid.
2. Phenols divided into mono-, di-, tri- tetra-, and polyhydric phenols,
e.g. p-chlorophenol, C6H4ClOH, 2, 4, 6-tribromophenol,
Chlorophenol red, C19H12Cl2O5S,
(acid-base indicator): 8.0 18.104.22.168a Pyrogallol, C6H3(OH)3,
1.2,3-trihydroxybenzene, white crystals, reducing agent, alkaline solution,
hydrogen carbonate not sodium hydroxide), reacts with oxygen in the
air to form a brown polymer.
Pyrogallol is used in experiments where oxygen must be eliminated
from a gas or from the air.
Pyrogallol is prepared by heating gallic acid, C6H2(OH)3COOH,
(3,4,5-trihydroxybenzoic acid). 22.214.171.124.1 Carbolic acid,
Benzene compounds: See diagram 16.8.1
1. Carbolic acid, C6H5OH, "phenol" from coal
tar fraction 170oC to 230oC, colourless hygroscopic
Phenol is acidic so ionizes in water:
C6H5OH --> H+ + C6H5O- Do not wash off with alcohol because carcinogenic products or
explosive materials may form.
To avoid carcinogenic by-products, use sulfuric acid, not hydrochloric
acid, as a catalyst to prepare polymers.
2. "Phenol", carbolic acid (C6H5OH), is a pale
pink crystalline solid, solid because of the hydrogen bonds between the
Pure phenol (carbolic acid) blisters the skin but it is still used
in carbolic soaps as an antiseptic.
Formerly, it was used as an antiseptic spray in early medical operations.
Other antiseptics and disinfectants include TCP (2.4.6-trichlorophenol),
and Dettol (4-chloro-3,5-dimethylphenol).
Phenol as a weak acid: phenol loses a proton, H+ ion, to form a phenoxide
Phenol reacts with alkalis: phenol + NaOH (aq) <=> sodium phenoxide
(aq) C6H5ONa + H2O.
Sodium phenolate, C6H5ONa.3H2O
Halogenation of phenol: phenol + bromine --> 2.4.6-tribromophenol,
phenol + chlorine --> 2-chlorophenol, C6H5OHCl
Chlorophenol red, C19H12Cl2O5S,
(acid-base indicator): 8.0
Carvacrol, cymophenol, C6H3CH3(OH)(C3H7),
monoterpenoid phenol, in oregano herb
3. TCP, was originally trichlorophenylmethyliodosalicyl, but nowadays
TCP contains various phenols. 126.96.36.199.2 Naphthols See diagram 188.8.131.52: Phenols, Quinones,
naphthols | See 184.108.40.206: Tests
for carbonates, Molisch's test (α-naphthol test)
1-naphthol, C10H7OH, a-naphthol, α-naphthol,
naphthalen-1-ol, tests for carbonates
2-naphthol, C10H7OH, b-naphthol, beta-naphthol,
naphthalen-2-ol, white solid, antioxidant in rubber products, antiseptic,
primary amines 220.127.116.11.3 Cresols See Cresylic acid,
CH3C6H4OH, "cresol, (mixture of the
three isomers of cresol)"
Cresols are methyl phenols, C7H8O, CH3C6H4OH,
produced from coal tar creosote or by methylation of phenol
"Cresol" used as a disinfectant is usually a cresol mixture: o-cresol,
Toxic by all routes
(o-Cresol, ortho-cresol, 2-Methylphenol), colourless crystals
(m-Cresol, meta-cresol, 3-Methylphenol), liquid
(p-Cresol, para-cresol, 4-Methylphenol), solid 18.104.22.168.4 Resorcinol,
Harmful, corrosive to skin See diagram 22.214.171.124: Resorcinol
Resorcinol, C6H4(OH)2, crystals,
resorcin, m-dihydroxybenzene, 1.3-dihydroxybenzene, benzene-1-3-diol,benzene-1-3-diol,
1.3 benzenediol, (a dihydroxy phenol)
Resorcinol, Solution <10%, Not hazardous, but do not ingest
Resorcinol, (test reagent in ethanol), explosive with nitric acid,
turns red in light, antiseptic, colourless crystals, used for cold-setting
adhesives with formaldehyde.
Prepare formaldehyde resorcinol resin: 126.96.36.199 188.8.131.52.5 Triclosan,
organohalogens See diagram 184.108.40.206: Triclosan
Triclosan, 5-chloro-2-(2,4-dichlorophenoxy) phenol, C12H7Cl3O2,
is an organohalogen polychlorophenoxy phenol used in
anti-bacterial and anti-fungal products, and in low concentrations
in many other products, including toothpaste, mouthwash, deodorants,
soap, scent, detergent dishwashing liquid, hand washes, at high concentrations
is harmful by inhalation, irritant, environmental danger
Triclosan is suspected of causing bacterial resistance because of
it widespread use and occurrence in the environment and may weaken
the immune system.
Other organohalogens include: 2, 4, 6-trichlorophenol, 2, 4, 6-tribromianisole,
2, 4, 6-trichloroanisole, chlorophenol compounds +
filamentous fungi --> 2, 4, 6-trichloroanisole. 220.127.116.11 Thiols (mercaptans) See diagram 18.104.22.168: Thiophenol (phenyl
mercaptan), | See diagram 16.13.10: Metam,
Thiols, thio-alcohols (RSH, R not equal to H), (sulfhydryl group:
-SH, characteristic of thiols).
(Suffix: -thiol), [old name: mercaptans, because react with mercuric
ion to produce mercaptides (RS)2Hg], e.g. methanethiol, methyl
mercaptan (CH3SH), ethanethiol (MeCH2SH), ethyl
mercaptan (ethanethiol or ethan-ethiol or captan), (C2H5SH),
thiophenol, phenyl mercaptan Ph-SH, sodium thiolate: (RS-Na+)
Thiols, RS-H, are oxidized to disulfides, RS-SR.
Methanethiol from asparagus
The methylmethionine and asparagusic acid, α-aminodimethyl-γ-butyrothetin,
in asparagus may produce malodorous methanethiol,
dimethyl disulfide and dimethyl sulfone in people who eat asparagus.
However, less than 50% of adults can smell these compounds in the
Family studies suggest that the ability to produce the odorous urine
is inherited as an autosomal dominant trait. 22.214.171.124.1 Methyl mercaptan,
methanethiol, CH3SH, (MeSH), colourless gas, very flammable,
offensive rotten cabbage or
decomposing vegetables smell in bad breath and flatus, in some nuts
and cheese 126.96.36.199.2 Allyl mercaptan,
flavouring agent, 2-propene-1-thiol, from garlic, C3H6S,
EC Number (EINECS): 870-23-5
Odour threshold value: 6 × 107 molecules / mL of air 188.8.131.52.3 Ethyl mercaptan,
ethanethiol, CH3CH2SH, colourless gas, offensive
rotten cabbage smell, poisonous and used as
odorant in LPG gas at less than poisonous concentration to allow early
detection of gas leaks
There is some evidence that very old men cannot smell it and so are
susceptible to LPG gas poisoning. 184.108.40.206.4 Thiophene,
thiolane, THT, (CH2)4S
Thiophene, tetrahydrothiophene, colourless, unpleasant odour gas,
used as odorant in natural gas and LPG gas, (not in USA) 220.127.116.11 Ethers 1.13 Ethers, List of ethers
Ethers have two hydrocarbon groups linked by one oxygen, and have
compounds in the form: R1OR2 (R not equal to H), where R1
may or may not be the same as R2, e.g. the anaesthetic diethyl ether. Ethers (ROR'), (CnH2n+2O), alkyl ethers,
ethoxyethane ether, e.g. dimethyl ether (CH3OCH3) 18.104.22.168 Ethyl cellulose
Ethyl cellulose, cellulose ethyl ether, food additive emulsifier E462,
prepared from cellulose in wood and chemically ethylated,
thickening agent, filler, dietary fibre, anti clumping agent, emulsifier
Ethyl cellulose is no longer permitted as emulsifier in the EU, can
be fermented in the large intestine to cause bloating, constipation and
diarrhoea. 22.214.171.124 Acetates (ethanoates),
ROAc, salt or ester of ethanoic acid (acetic acid)
As a salt: sodium acetate, sodium ethanoate (CH3COONa).
As an ester: ethyl ethanoate (CH3COOC2H5)
126.96.36.199 Benzoyl group,
benzene carbonyl group C6H5CO-
e.g. benzoyl chloride (C6H5COCl) 188.8.131.52 Acetal (alcohol
+ aldehyde), RCH(OR')2, where R and R' = organic radicals
and R may be hydrogen
Acetal, 1.1-diethoxy ethane, CH3CH(OC2H5)2,
is a colourless flammable solvent, smelly liquid
It is formed by reaction of acetaldehyde with ethanol.
Hemiacetals: [RCH(OH)R'], Di-methyl acetals: [RC(OMe)2R'],
Di-ethyl acetals: [RC(OEt)2R'] (polyacetals, polyoxymethylene
POM) 184.108.40.206 Salts, e.g. sodium
ethanoate (sodium acetate) (CH3COONa), ammonium acetate (CH3COONH4)
NaHCO3 + CH3COOH --> CH3COONa
+ H2O + CO2 (g) 220.127.116.11 Saturated hydrocarbons,
e.g. hexane, C6H14
All carbon atoms in the compound have either four or three hydrogens
bonded to them and no double bonds, triple bonds or rings.
They react in almost the same way, as in ignition test and bromine
water test. 18.104.22.168 Tests for unsaturated
hydrocarbons, bromine water tests for unsaturation 22.214.171.124 Tests for unsaturated
hydrocarbons, ignition tests for unsaturation 126.96.36.199 Acyl halide, acid
chloride, Acid chlorides group: (-COCL), Suffix: -oyl chloride
acyl chloride (RCOCl), e.g. ethanoyl chloride (acetyl chloride), (CH3COCl) 188.8.131.52 Amides, acid amides
(-amide), (amide group: -CONH2, RCONH2)
e.g. urea (H2NC=ONH2)
[IUPAC: Do NOT distinguish amides with NH2, NHR, NR2
groups by the terms "primary, secondary, tertiary".]
1. Primary amides RCONH2, e.g. alkanamides: ethanamide
(acetamide), (CH3CONH2) propanamide (C2H5CONH2)
2. Secondary amides, N-substituted amides RCONHR'
3. Tertiary amides RCNR'R"
Secondary or tertiary amides have the prefix N, e.g. N-ethylethanamide
N.N-dimethylmethanamide HCON(CH3)2 (the polymer
group -CO-NH-), (inorganic amides, e.g. KNH2) 184.108.40.206a Carbamates See diagram 16.13.7: Carbamates, carbaryl,
Carbamates are derivatives of carbamic acid, NH2COOH.
Urethanes are esters of carbamic acid, i.e. alkyl carbamates.
Examples of cabamates: carbamic acid, ammonium carbamate, bendiocarb,
carbaryl, oxamyl, propoxur, urethane.
Combustion of carbamates may produce noxious NOx and carbon monoxide.
Carbametes are more reactive than amides and can form polyurethane
Carbamates are incompatible with strong acids and bases, strong oxidizing
acids, and peroxides.
Many carbamates are used as pesticides because of their anticholinesterase
activity, e.g. carbaryl, propoxur, bendiocarb and methomyl. 220.127.116.11.01 Physostigmine
From Calabar bean, (Physostigma venenosum), alkaloid C15H21N3O2,
poison bean but used in pharmacy for depression, antidote
for belladonna poisoning, and cholinesterase inhibitor. 18.104.22.168.1 Acrylamide,
C3H5NO, 2-propenamide, ethylene carboxamide, acrylic
amide, propenoic acid, UN 2074, vinyl amide is
toxic if ingested, crystalline form and aqueous solutions, monomer
Acrylamide, C3H5NO, CH2CHCONH2,
is the amide of acrylic acid, propenoic acid, (CH2CHCOOH),
an unsaturated liquid
Acrylamide is a poison, harmful if swallowed, inhaled or absorbed
through skin, affects central and peripheral nervous systems and
It causes irritation to skin, eyes and respiratory tract, suspected
cancer hazard depending on level and duration of exposure,
possible birth defect hazard.
It is thermally unstable, but can polymerize explosively if heated
to the melting point.
It is most common in overcooked French fries and potato chips, also
burned toast and burned high carbohydrate foods.
The European Food Safety Authority (EFSA) recommends consuming golden
rather than dark brown or black toast, short expresso
rather than lungo, and avoiding overcooked foods. 22.214.171.124 Acid anhydrides,
acyl anhydrides, anhydrides [RCO-O-COR' (R(C=O)O(C=O)R')]
e.g. ethanoic anhydride (acetic anhydride), [(CH3CO)2O],
ethanoic anhydride [CH3(C=O)O(C=O)CH3],
trifluoroethanoic propanoic anhydride [CH3CH2(C=O)O(C=O)CF3] 126.96.36.199 Imides (R1CO-NH-COR2),
(imido group: -CONHCO-), e.g. gluthemide (C13H15NO2).
The polymer group (-CO-NR-CO), polyimides, N-(trichloromethylthio),
cyclohex-4-ene-1. 2-dicarboyimide 16.1.12
Fractional distillation of crude oil
A fractionating column is used to separate the distillates that boil
within a temperature range, i.e. the "fractions".
Fractional distillation of crude oil: petroleum gas (LPG), naphtha,
petrol (gasoline), kerosene (paraffin oil), diesel oil, lubricating oil
(motor oil), paraffin wax (fuel oil), residuals (bitumen, "tar", asphalt,
The word "asphalt" can refer to natural bituminous pitch, e.g. the
Trinidad Pitch Lake, or the fraction of crude oil produced by
distillation or the "hot mix" mixture of aggregate and bitumen used
to surface roads, paths and school playgrounds. 188.8.131.52 Petroleum gas
(methane, ethane, propane, butane)
Mix of 1 to 4 carbon atoms, boiling range < 40oC.
Liquefied under pressure as LPG (liquefied petroleum gas), a mixture
mainly of propane (C3H8), and butane (C4H10). 184.108.40.206 Naphtha (petroleum
naphtha, ligroin), processed to make gasoline
Mix of 5 to 9 carbon atoms, mainly aliphatic, e.g. alkanes, boiling
range 120oC to 180oC, or < 200oC.
The light hydrocarbon cut between gasoline and kerosene.
(Another naphtha can also be produced from coal tar.) 220.127.116.11 Petrol, "gas",
gasoline, motor fuel
Mix of C6H14 to C11H24,
5 to 12 carbon atoms, alkanes and cycloalkanes, boiling range 40 to 205oC 18.104.22.168 Kerosene, kerosine,
paraffin oil, jet engine fuel, tractor fuel
Mix of C12H26 to C15H32,
10 to 18 carbon atoms, alkanes and aromatics, boiling range 175oC
to 325oC 22.214.171.124 Diesel oil, gas
oil or diesel distillate, diesel fuel, heating oil
Mix of C15H32 to C18H38,
12 or more carbon atoms, alkanes, boiling range 250oC to 350oC 126.96.36.199 Lubricating oil,
motor oil, grease
Mix of C16H34 to C24H50, 20
to 50 carbon atoms, alkanes and cycloalkanes and aromatics, boiling range
300oC to 370oC 188.8.131.52 Paraffin wax,
heavy gas, fuel oil
Mix of C20H42 and higher hydrocarbons, 20 to
70 carbon atoms, alkanes and cycloalkanes and aromatics, boiling range
370oC to 600oC 184.108.40.206 Residuals, bitumen,
"tar", asphalt, waxes
A mix of C24H50 and higher hydrocarbons, multiple-ringed
compounds, 70 or more carbon atoms, boiling range > 600oC
Petroleum jelly is a saturated semi-solid of crystalline
and liquid hydrocarbons, carbon numbers < C25, made by dewaxing paraffinic
Naphtha, "Greek fire", was an inflammable bituminous substance used
in warfare. 16.1.13 Prepare triodomethane
(iodoform) See 1.6: Iodine solution | See diagram 16.2.2: Halogen compounds, haloalkanes
Add five drops of iodine solution to five drops of ethanol.
Add drops of dilute sodium hydroxide solution until the brown colour
of iodine disappears.
Observe the crystals under a microscope.
C2H5OH + 4I2 + 6NaOH --> HCOONa
+ 5NaI + 5H2O + CHI3
ethanol + iodine + sodium hydroxide --> sodium methanoate (sodium
formate) + sodium iodide + water + triodomethane (iodoform) 16.1.14 Prepare trichloromethane
(chloroform) See: Trichloromethane,
chloroform See diagram 16.1.7: Prepare chloroform
| See 16.2.2: Chlorinated hydrocarbons, haloalkanes
Bleaching powder is usually a mixture of calcium chlorate (I) [basic
calcium chloride, calcium hypochlorite], calcium chloride and
calcium hydroxide prepared by passing chlorine gas through a calcium
Calcium chlorate (I) oxidizes ethanol to ethyl aldehyde.
Aldehydes or ketones have a hydrogen atom attached to the carbon atom
attached to the carbonyl group, C=O.
This hydrogen atom can be replaced by a halogen atom to form halogen
If a molecule contains three such hydrogen atoms, e.g. ethanol and
propanone (acetone) molecule, a trihalide may be formed,
e.g. trichloromethane (chloroform, CCl3).
H3C-C(O)-R + 3OX --> X3C-C(O)-R
ketone or aldehyde hypochlorite --> trihalide
The trihalide decomposes in a basic solution to a haloform (CHX3),
e.g. CHCl3C-C(O)-R (l) + OH- (aq) --> CHCl3
(l) + RCOO- (aq) 220.127.116.11 Reaction of acetone
with bleaching powder
CH3COCH3 + 3Cl2 --> CCl3COCH3
2CCl3COCH3 + Ca(OH)2 --> 2CHCl3
Ca(OH)2 + 2HCl --> CaCl2 + 2H2O 18.104.22.168 Reaction of ethyl
alcohol with bleaching powder
C2H5OH (l) + Cl2 (g) --> CH3CHO
(l) + 2HCl (aq)
ethyl alcohol + chlorine --> ethyl aldehyde
CH3CHO (l) + 3Cl2 (g) --> CCl3CHO
(l) + 3HCl (aq)
2CCl3CHO (l) + Ca(OH)2 (aq) --> 2CHCl3
(l) + (HCOO)2Ca (aq)
Be careful! Do not allow any flames in the
Grind together in a mortar and pestle 5 g bleaching powder and 10
Put the mixture into the test-tube of the gas preparation apparatus.
Cool the test-tube.
Add either 4 mL ethanol in 2 mL water or 4 mL propanone (acetone)
in 2 mL of water.
Swirl the contents of the test-tube and keep it cool. Use an electric
water bath to warm the temperature to 55oC.
Water and trichloromethane condense in the receiving test-tube leaving
a calcium salt solution in the test-tube.
Add water to the distillate and separate the trichloromethane with
a separating funnel. 16.2.2 Halogen compounds,
haloalkanes (alkyl halides), halogen derivatives
| See diagram 16.2.2: Chlorinated hydrocarbons,
methyl chloride, methylene chloride, chloroform, carbon tetrachloride
| See diagram: 16.13.5: Bifenox, dicofol,
naled, trichlorophon, tetrachlorvinphos
| See diagram 16.13.11: MCPA, 2, 4-D,
2, 4, 5-T, picloram
Acyl halides, (acid halides; RCOX, where X = halide group and R =
organic group, e.g. acetyl = CH3CO-)
Haloforms, e.g. trihalomethanes CHX3 Alkanes react with chlorine and bromine in ultraviolet light
to produce haloalkanes, e.g. 2-chloropropane.
Reactions of chlorine or bromine in ultraviolet light
CH4 + Br2 --> CH3Br + HBr
CH3Br + Br2 -->CH2Br2
CH2Br2 + Br2 --> CHBr3
CHBr3 + Br2 -->CBr4 + HBr 1.0 Chlorine compounds
acyl chlorides, acid chlorides (acyl = RC=O-)
ethanoyls (-COCl), (-oyl chloride), ethanoyl chloride (acetyl chloride),
chloroform CHCl3, chloromethane (methyl chloride), (CH3Cl)
ethylene dichloride (1.2-dichloroethane, Freon 150), (ClH2C-CH2Cl)
chloroethene (vinyl chloride) (CH2:CHCl)
tetrachloromethane (carbon tetrachloride), (CCl4)
phosgene (carbonyl dichloride), COCl2 chlorine + sulfur: thiophosgene (thiocarbonyl dichloride), (CSCl2)
chlorine + OH: dicofol, MCPA, 2, 4-D, 2, 4, 5-T,
chlorine + N: Bifenox, chlorine + P: trichlorophon, tetrachlorvinphos 2.0 Iodine compounds
iodoform (tri-iodomethane), (CHI3), iodoethane (CH3CH2I) 3.0 Bromine compounds
bromoform (CHBr3), ethyl bromide (bromoethane), (C2H5Br),
ethylene dibromide (1:2-dibromoethane)
Halons (fire extinguishers): Halon-1211 bromochlorodifluoromethane
(CBrClF2), Halon-1301 bromotrifluoromethane (CBrF3) 4.0 Fluorine compounds
fluoroform (CHF3), tetrafluoroethene (CF2CF2),
polytetrafluoroethene (PTFE, Teflon), Repeat unit: -[CF2=CF2]n-,
C2F4 Teflon, polytetrafluoroethylene, poly(1.1.2,2-tetrafluoroethylene),
is a synthetic fluoropolymer of tetrafluoroethylene. 5.0 Magnesium with PTFE, polytetrafluoroethylene,
aircraft flares, heat-seeking missile decoys
2n Mg + (C2F4)n --> 2n MgF2(s)
+ 2n C(s) 6.0 Chlorofluorocarbons, CFCs
(old name = Freons)
CFC-11 trichlorofluoromethane (CCl3F), CFC-12 dichlorodifluoromethane
See "Freons": 22.214.171.124 16.2.3 Organometal compounds
(prefix the metal with organo-), e.g. organomagnesium compounds.
MeMgI iodo(methyl)magnesium, Et2Mg diethylmagnesium 126.96.36.199 Carbides, C4-
Carbide are binary compounds of:
1. C + electropositive element, e.g. calcium carbide.
2. C + heavy metal for cutting tools, e.g. aluminium carbide (Al4C3),
chromium carbide, Cr3C2, iron carbide Fe3C
Tungsten carbide ("carbide", WC), is used for cutting tools, milling
tools, abrasives, jewellery.
Iron carbide is formed with carbon monoxide when iron oxide is heated
3Fe2O3 +11C --> 2Fe3C + 9CO (g) Types of carbides 1. Methanides, e.g. aluminium carbide, Al4C3
Hydrocarbyl anions, methyl anion, conjugate base of methane
Methanides + water --> methane, e.g. aluminium carbide, (Al4C3) 2. Acetylides, salts of
acetylide anion C22- (percarbide)
Formed by alkali metals, alkaline earth metals, lanthanoid metals,
e.g. sodium carbide Na2C2, copper (I) acetylide Cu2C2,
lanthanum carbide LaC2, aluminium carbide Al4C3,
calcium acetylide CaC2, cementite Fe3C (iron carbide),
copper (I) acetylide
Acetylides (percarbides, C22-) + water -->
acetylene, e.g. Na2C2, CaC2
Calcium carbide CaC2, (calcium dicarbide, "carbide", calcium
acetylide, acetylenogen, ethnide dicarbide, Toxic by all routes
CaC2 + 2H2O --> C2H2
calcium carbide + water --> acetylene + calcium hydroxide 3. Sesquicarbides,
C34-, e.g. Mg2C3 4. Covalent carbides,
e.g. boron carbide B4C, silicon carbide, SiC, (carborundum)
See: Models, inorganic,
carborundum, (silicon carbide), 30 "atoms", "Scientrific" (Commercial)
Silicon carbide, SiC, carborundum, abrasive, moissanite synthetic
gemstone, emery paper, sanding paper, sharpening stone, fine
particles, Toxic by inhalation 16.2.4 Nitrogen compounds,
one atom of nitrogen See 188.8.131.52: Amides 184.108.40.206 Nitriles
Nitriles (acid nitriles, alkyl cyanides, cyanides), (-CN, RCN), (note
triple bond), Cyanide ion: CN- e.g. ethane nitrile (methyl cyanide,
ascetonitrile) (CH3CN), 5-methoxyhexanenitrile, [CH3C(OCH3)HCH2CH2CH2CN],
acrylonitrile for making Orlon (vinyl cyanide, 1-cyanoethene), (CH2=CH-CN) 220.127.116.11.1 Cyanamides,
(inorganic, CN22-), ionization reaction of methylamine See diagram 18.104.22.168.1: Melamine
cyanic acid (fulminic acid), (HOCCN), (cyanates, fulminates), Isocyanic
acid (H-N=C=O), isocyanates
(isocyanate group: -NCO, HN=C=O), isocyanides (HNC), hydrocyanic acid
CaCn2 + H2O + CO2 --> H2NCN
calcium cyanamide + water + carbon dioxide --> cyanamide + calcium
(NH2)2CO --> HCNO + NH3
urea --> cyanic acid + ammonia
6HCNO --> C3H6N6 + 3CO2
cyanic acid --> melamine + carbon dioxide
6(NH2)CO --> C3H6N6
+ 6NH3 + 3CO2
Melamine, C3H6N6, 2,4,6-triamino-1.3,5-triazine
is 66% nitrogen w/w and is used in the plastics industry.
Unfortunately, its high nitrogen content has been the reason for its
use as a powdered milk pollutant in China resulting in death and
kidney problems in young babies due to the formation of kidney stones.
Melamine-formaldehyde, (MF), C4H6N6O,
hard to ignite, alkaline fumes, burns with pale yellow flame (light blue-green
formaldehyde and fish-like smell, thermosetting plastic, retains strength
and shape on heating
Melamine crockery, green, virtually unbreakable, dishwasher safe,
Not suitable for microwave oven, plate, 18 mm diameter 22.214.171.124.00 Amines, aliphatic
amines (RNH2-, R = alkyl group), ionization reaction
Amines have lower boiling temperatures than alcohols.
Methylamine and ethylamine are gases at room temperature.
Longer chain amines are volatile liquids with rotten fishy smells
characteristic of decomposing proteins
Amines are bases, (can accept a H+ ion), so can react with
acids to form salts and lose the fishy smell.
1. Primary amines: R-NH2
NH2- = amino group, e.g. methylamine (CH3-NH2),
ethylamine (CH3CH2-NH2). Aniline, phenylamine C6H5NH2,
has a benzene ring
2. Secondary amines: R2-NH
NH = imino group, e.g. dimethylamine (CH3)2NH
3. Tertiary amines: R3-N
N = nitrogen, e.g. trimethylamine (CH3)3N, triethylamine,
(C2H5)3N 126.96.36.199.01 Methylamine
CH3NH2 + H2O <--> CH3NH3+
+ OH- methylamine + water <--> methylammonium ion + hydroxide
ion 188.8.131.52.02 Prepare phenylamine
1. Benzene + concentrated nitric acid + concentrated sulfuric acid
--> nitrobenzene, C6H5NO2
2. Nitrobenzene + tin catalyst Sn + reducing agent hydrochloric acid
--> phenylamine + water
C6H5NO2 + 6 H+ -->
C6H5NH2 + 2H2O 184.108.40.206.03 Nitrosamines
Nitrosamines are produced by reaction of nitrous acid with secondary
They can be formed in the gut when nitrites react with amino acids.
C4 explosive, H8N8O8, HMX, Octogen,
detonator, solid rocket propellant, mainly cyclonite or cyclotrimethylene
RDX explosive (Research Department Explosive, C3H6N6O6,
Cyclonite, Hexagen, used against German submarines during World
War II 220.127.116.11.04 Nitramine Nitramine, (acid-base indicator, 3.5),
C7H5N5O8, tetryl. colourless-yellow
crystals, explosive formerly used in munitions 18.104.22.168.05 Clenbuterol,
Performancing-enhancing drug banned by the International Olympic Committee.
It is illegally used to build skeletal muscle and increase metabolism,
but may cause heart attacks.
Clenbuterol is a substituted phenylaminoethanol that has beta-2 adrenomimetic
properties at very low doses.
It is used as a bronchodilator in asthma.
Although approved for use in some countries, as 2006 clenbuterol is
not an ingredient of any therapeutic drug approved by the US
Food and Drug Administration. 22.214.171.124.1 Ethylenediamine
ClCH2CH2Cl + 4 NH3 --> H2NCH2CH2NH2
+ 2 NH4Cl
1.2-dichloroethane + ammonia --> ethylenediamine + ammonium chloride 126.96.36.199a Imines
Imino group = ring containing (-NH-), or (=NH), linked to C], (RN=CR',
where R = H or hydrocarbyl,
e.g. (ethyl-), 0-benzoquinonedimine
Imine primary RC(=NH)R (imino-), (-imine)
Imine secondary RCH=NR (imino-), (-imine) 188.8.131.52 Nitroalkanes (nitroparaffins),
Nitromethane (CH3NO2), nitroethane, urea (carbamide) 184.108.40.206 Nitrites
(NO2-), dioxonitrate ion, salts or esters of nitrous acid,
Nitrites group: -C=N, Suffix: -nitrite, , e.g. sodium nitrite and
potassium nitrite used
as meat curing agents 220.127.116.11 Oximes (hydrox-imino-alkanes)
Formula R1R2C=NOH, where R1= organic side chain and if R2 = hydrogen,
aldoxime forms or if R2 = organic group, ketoxime forms.
(-CNOH group), (ketone or aldehyde + hydroxylamine - water), (RCNOHR'),
e.g. ethanal oxime (acetaldehyde oxime, AAO),
(CH3CH=NOH) 18.104.22.168 Cyanocrylates
e.g. "Superglue": Me or Et ester
Ethyl cyanoacrylate, "Superglue", BE CAREFUL! Do not squirt in the
eye! Toxic by all routes.
Commercial: Ethyl 2-cyanoacrylate, liquid, C6H7NO2
GBL, γ-butyrolactone is a naturally occurring colourless oily liquid
with a characteristic odour used as a stain remover and stripper,
(including Superglue). 22.214.171.124 Azide compounds
Azide compounds: (N3-), or (-N3),
(-N=N+N-), usually attached to carbon, e.g. sodium azide (NaN3),
phenyl azide or azidobenzene
(C6H5N3), diazine (diimide) (HN=NH),
also, salts of hydrazoic acid, HN3, e.g. sodium azide (NaN3). 126.96.36.199 Azo compounds
Azo compounds: derivatives of diazene (diimide), HN=NH, with both
hydrogens substituted by hydrocarbyl groups, e.g. azobenzene
or diphenyldiazene (PhN=NPh).
hydrazone (ketone + hydrazine (N2H4) - water),
(RC=NNH2R') See: 3.0 Benzopurpurin 188.8.131.52 Diazo compounds
Diazonium ion R-N+N, diazonium compounds [(RNN+)
Cl-], e.g. diazomethane (CH2=N2)
HNO2 and HCl + R-NH2 --> R-N+N + Cl-
nitrous acid and hydrochloric acid + amines --> diazonium ion +
HNO2 + HCl + C6H5NH2 -->
C6H5N2Cl + 2H2O
nitrous acid and hydrochloric acid + phenylamine --> benzenediazonium
chloride + water
benzenediazonium chloride + phenol --> 4-(phenylazo)phenol + NaCl
benzene-N+NCl- + H-benzene-OH + NaOH -->
benzene-N=N-Benzene-OH + NaCl + H2O
4-(phenylazo) phenol is a yellow dye
Azo dyes of the textile industry use diazonium salts.
The material is first soaked in a soluble salt of phenol or naphthol
then soaked in a diazonium salt so that the dye forms in the cloth. 184.108.40.206 Phenylhydrozone
Phenylhydrozone [RC=N(NH), (Phenyl group) R'], (ketone or aldehyde
+ phenylhydrazine, [C6H5(NH)NH2] - water).
2, 4-dinitrophenylhydrozone, semicarbazone [RC=N(NH)CO(NH2)R'] 16.2.6 Phosphorous compounds,
Captan fungicide: 16.6.3
Organophosphorus insecticides (mostly thiophosphates), TEPP (tetraethylpyrophosphate,
no longer used as insecticide), parathion,
maldison (Malathion), dimethoate (Rogor), dichlorvos (dimethyl dichlorovinyl
phosphate, DDVP, Shelltox strips), demetron (Systox)
Organophosphates, acephate, dichlorvos, dimethoate, malathion (maldison),
parathion See diagram 16.13.6: Benomyl, captan,
1. Phosphonic acid, phosphorous acid [HPO(OH2), H3PO3]
2. Phosphonoglycine, N-(phosphonomethyl) glycine, glyphosate (in "Roundup"
3. Organic phosphates: acephate, diazinon, dichlorvos, dimethoate,
malathion (maldison), naled, parathion
(old name: mustard oil), (RN=C=S), mustards [X(CH2.CH2)2S]
Allyl isothiocyanate (AITC), CH2CHCH2NCS, colourless
oil, taste of mustard, horseradish, wasabi 220.127.116.11 Sulfides
Sulfides: RSR (R not equal to H), (old name: thioethers)
Diallyl disulfide C6H10S2, organosulfur
compound, from garlic and other Allium species, Alliaceae.
People who eat asparagus may notice a malodorous over-boiled cabbage
smell in their urine because of sulfur compounds,
e.g. diallyl disulfide, dimethyl sulfide, dimethylsulfone, sulfimides
Oil of garlic contains diallyl disulfide, diallyl trisulfide and diallyl
tetrasulfide, crushing garlic produces allicin, C6H10OS2.
Diallyl disulfide has health benefits for most people, but some people
are allergic to it and most Allium species. 18.104.22.168 Sulfonium compounds:
Sulfonium salts, e.g. trimethylsulfonium chloride [(CH3)3S]+Cl-,
Cyclopropyldiphenylsulfonium tetrafluoroborate, C15H15BF4S 22.214.171.124 Thiocyanates:
[RC(=O)SN] salts and esters of thiocyanic acid HSCN, e.g. methyl thiocyanate
(CH3SCN) 126.96.36.199 Siloxanes
Saturated silicon-oxygen hydrides with chains of alternating silicon
and oxygen atoms, e.g. unbranched [H3Si(OSiH2)nOSiH3],
"Volasil" is octamethylcyclotetrasiloxane.
Dimethylpolysiloxane is an anti-caking agent, emulsifier and anti-foaming
agent. 188.8.131.52 Sulfoxide, RS(=O)R'
1. Propanethial S-oxide, C3H6OS, lachrymatory
factor from cut onion cells, Allium cepa, formed when enzyme allinase
S-1-propenyl-L-cysteine sulfoxide, hydrolyses to propanol, H2SO4,
H2S, so stings the eyes.
2. Dimethyl sulfoxide, (DMSO, (CH3)2SO, C2H6OS)
3. L-Alliin, C6H11NO3S, ACSO, S-Allyl-L-cysteine
sulfoxide, SAC 16.2.10 Coal tar products,
Chemicals produced from destructive distillation of coal when making
coke for steel production.
Many organic compounds can be isolated by distillation of coal tar
but many are now made from petroleum or natural gas.
The residue of coal tar distillation is called pitch and is used for
road tar and waterproofing of roof material.
The residue of petroleum distillation is called asphalt but also called
Coal tar paints resist heat and moisture.
Coal tar dyes, called azo dyes, are made from azobenzene and were
used as food colourings.
Coal tar products include:
1. hydrocarbon oils, e.g. benzene, toluene, xylene
2. phenols, e.g. carbolic acid, and
Coal tar is a creosol mixture that includes 2-hydroxytoluene, 3-hydroxytoluene,
It sensitizes skin to sunlight, so use gloves because it may cause
It is used as a wood preservative of railway sleepers, telegraph poles.,
fungicide, soap for treatment of skin diseases, and sheep dip
However, wood creosote is a mixture of phenols of wood tar and is
used as a disinfectant, cough medicine, diarrhoea medicine,
preservative, and antiseptic.