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The USES and APPLICATIONS of CHEMICALS

Uses of Elements, compounds or Mixtures (1st draft)

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PAGE INTRODUCTION - PLEASE READ first! This web page consists of an ALPHABETICAL LIST of 220 elements, compounds or mixtures with a brief description of their properties and uses. You can quickly scroll down through them using the 'page up or page down key' or click on the first letter index below.

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

This list is very much about what is around you or close by geographically. Not only are you a complex biochemical system yourself, but much of your 'environment' in its widest cultural and technological sense depends on chemistry and its many applications. The proof is just to browse down this 'humble' list, which only contains a tiny fraction of the millions of different chemical compounds that exist, both naturally and manmade whether used in the chemical industry, the environment or a household product. Can I 'emphasise' that the 'emphasis' in this list is how different materials have different uses without going into excessive detail and there are lots of 'cross-links' on this page for inter-related material uses and links to more detailed notes where available. There are no graphic images so as to reduce the download time of this extensive and long page. Issues relating to the use of the listed materials may be mentioned here or elsewhere on the website. I hope this alphabetical list will prove useful as a quick brief and preliminary research resource or revision study notes for pupils/students of KS3 science, GCSE/IGCSE/KS4 Science, GCSE/IGCSE Chemistry, GCE-AS-A2-IB Advanced Level Chemistry and US science-chemistry K12 grades 6-12 and other equivalent courses.

SUBSTANCES in alphabetical order	STRUCTURE and PROPERTIES	TYPICAL EXAMPLES of USES of the substance which you should be able you relate to the substances structure and properties
A materials ACETIC ACID and VINEGAR	See ETHANOIC ACID for uses.	More on carboxylic acids at GCSE Extra Organic Chemistry Notes, see also ESTERS and CARBOXYLIC ACIDS.
ACIDS HCl,HNO₃, H₂SO₄ CH₃COOH etc.	Compounds containing an 'acidic' H that can be replaced by a metal. Acids react with metals, oxides, hydroxides and carbonates to form salts. If soluble n water give a pH < 7.	Uses of acids: Look up individual acids by name for their uses, too many to list here. Detailed chemistry notes on Acids, Bases, Alkalis, pH, Neutralisation & Salts GCSE Revision Notes
ACRYLIC MATERIALS e.g. polymethylmethacrylate (PMMA), man-made organic polymers.	Large organic molecules formed by polymerising unsaturated molecules (alkenes with the C=C double carbon=carbon bond group) such as methyl acrylate (methyl propenoate), methyl methylacrylate (methyl 2-methyl propenoate), acrylonitrile (propenenitrile), acrylic acid (propenoic acid). PMMA when cast in sheets has the trade name Perspex.	Uses of acrylic materials: They make tough flexible plastics or sticky resins that can solidified in context e.g. paints, moulded bone substitute. These resins and plastics have a huge range of uses. Poly(methyl acrylate) is used in emulsion form in textile and leather finishes, lacquers, paints, adhesives and safety glass layers (can replace glass in many situations). Poly(methyl methylacrylate), PMMA is a clear plastic material (Perspex) which can be injection moulded and extruded into a variety of products e.g. transparent impact resistant screens like car headlamps-aircraft windows, aquarium tanks, eye lenses, bone substitutes, signs. Acrylic paints consist of PMMA 'resin' suspended in water mixed with the colour pigment. Polyacryonitrile is used to make artificial fibres and elastomers (materials with elastic rubbery properties) for the textile industry.
ALCOHOLS (compounds) e.g. CH₃OH, CH₃CH₂OH etc.	Organic compounds of C, H and O atoms forming a homologous series of molecules containing the hydroxyl functional group -OH. They are colourless molecular liquids at room temperature.	Uses of alcohols: Wide range of uses e.g. fuels, solvents, esters, starting molecule to make other molecules. Best to see methanol, ethanol ('alcohol') and esters.
ALKALIS	Dissolve in water to give alkaline solutions of pH > 7 because the hydroxide ion, OH^-, is formed.	Uses of alkalis: Best to look up individual acids by name for their uses e.g. sodium hydroxide, calcium hydroxide. Their single biggest function is to make salts by reaction with acids. Detailed chemistry notes at Acids, Bases, Alkalis, pH, Neutralisation & Salts GCSE Revision Notes
ALKALI METALS	Group 1 elements of the periodic table.	Uses of alkali metals: See individual metals and their compounds e.g. sodium, sodium chloride etc.
ALKALINE EARTH METALS	Group 2 elements of the periodic table.	Uses of alkaline earth metals: See individual metals and their compounds e.g. calcium, calcium carbonate etc.
ALKANES (compounds) Homologous series of hydrocarbon compounds of general formula C_nH_2n+2 where n = 1, 2, 3 etc.	Covalent saturated hydrocarbon molecules consisting of combinations of carbon and hydrogen atoms. Flammable, smelly colourless gases or liquids or white waxy solids of little odour, depending on the value of n.	Uses of alkanes: Widely used as fuels from natural gas, petrol, central heating oil, paraffin/candle wax etc. see also methane, ethane, propane, butane and GCSE notes on Oil and its useful products
ALKENES (compounds) Homologous series of hydrocarbon compounds of general formula C_nH_2n where n = 2, 3, 4 etc.	They are small unsaturated covalent hydrocarbon molecules of carbon and hydrogen atoms. They have a C=C double bond which makes them reactive. The first few in the series are the most useful and are pungent smelling colourless gases.	Uses of alkenes: Alkenes are not used directly for anything BUT they are readily converted to other very useful organic molecules e.g. you can add water to make ethanol, as unsaturated monomer molecules they can be polymerised to make useful polymer-plastic materials called poly('alkene name') e.g. ethene makes poly(ethene). See also ethene, propene and GCSE notes on Oil and its useful products
ALLOYS a mixture of metal atoms with other metal or non-metal atoms	Huge range of mainly solid (sometimes liquids) mixtures of a metal mixed with other metals or non-metals. They are good conductors of heat/electricity but can have a wide variety of strengths and melting points. Metal structure & properties notes	Uses of alloys: Huge range, need to look up individual alloys in this list or elsewhere. By varying the mixture you can design an alloy material to suit a wide range of applications and uses e.g. alloys like steel, brass, nitinol/NiTi,
ALUMINIUM (aluminum, element) Al atoms	Relative low density ('light'), quite strong, high melting metal and a good conductor of heat and electricity. See Metal structure & properties notes and Al is obtained from bauxite ore, see Extraction of Metals	Uses of aluminium: Used for electrical power lines-cables (with copper), saucepans (less so, aluminium ions are harmful if aluminium dissolves in fruit juices), many alloys e.g. with magnesium to make strong light metal fabrication products like aircraft wings, food and drink containers and kitchen foil.
ALUMINIUM HYDROXIDE (compound) Al(OH)₃	It is an amphoteric hydroxide, and with acids it will react as a mild base to neutralise acids - hence its use as in ant-acid medicines.	Uses of aluminium hydroxide: Used in antacid mixtures because it will neutralise acids.
AMALGAM (mixture of metal atoms)	Alloy mixture of mercury and other metals.	Uses of amalgam: Initially prepared by the dentist as a paste which solidifies to make a dental filling.
AMINO ACIDS (organic compound)	These covalent molecules usually contain a carboxylic group (-COOH) and the amino group (-NH₂). When pure they are colourless crystalline substances which usually dissolve in water.	Uses of amino acids: The body needs amino acids and gets them from the digestion of protein from meat, fish, eggs, cheese and grain etc. The body then uses them to build up its own required protein structures from muscle fibres to enzymes.
AMMONIA and AMMONIUM SALTS (compounds) NH₃ molecules NH₄... compounds	Ammonia is a small covalent molecule of nitrogen and hydrogen. Its a colourless pungent smelling gas that is very soluble in water. It is a base/alkali and reacts with acids to form salts. Ammonium salts are colourless ionic crystalline solids which are soluble in water.	Uses of ammonia: Neutralised by acids fertilisers such as ammonium sulphate and ammonium nitrate to provide plants with the essential element nitrogen. It is oxidised (plus water) to manufacture nitric acid which is used in fertiliser and organic dyestuff manufacture. Ammonia is used in nylon manufacture and the aqueous solution used in the home in oven cleaning products. Uses of ammonium salts: Ammonium chloride paste is the electrolyte in zinc carbon batteries. As already mentioned - typical fertiliser salts ammonium nitrate, ammonium sulphate and ammonium phosphate. See GCSE notes on Ammonia and Nitric Acid and Acids, Bases, Alkalis, pH, Neutralisation & Salts GCSE Revision Notes
ANTIOXIDANTS (usually organic compounds, naturally found and manmade)	These are usually organic molecules with quite variable molecular structure. They slow down oxidation rates in auto-oxidisable substances by removing highly reactive species like free radicals.	Uses of antioxidants: They are added to protect/preserve foods, particularly those containing fat. They are used to reduce the ageing/deterioration of rubber and plastics. The body needs anti-oxidants to reduce the potential harm of free radicals. Vitamins C and E function as antioxidants and must fruits and vegetables contain antioxidants.
ANTISEPTICS (usually organic compounds)	Usually organic molecules, often based on phenol. Dettol and TCP antiseptics are formulations of chlorinated phenol molecules. Ethanol and iodine have powerful antiseptic properties.	Antiseptics kill microorganisms but are safe enough to use on the skin. Ethanol is widely used in hand washes in hospitals and iodine is a disinfectant for surgical procedures e.g. for treating skin prior to an operation. They are not as strong acting as disinfectants and can be used safely on skin and other tissue cells you wish to leave unharmed.
ARGON (element) Ar atoms	Colourless chemically unreactive gas ('inert') belong to the 'Noble Gases' Group 0 of the Periodic Table.	Uses of argon: It is its chemical inertness that makes them so useful. A small amount is in light bulbs to minimise evaporation of the metal at the high temperatures of the filament but will not oxides the metal. It is used in steel making by bubbling it through the mixture to allow stirring of the mixture and prevent oxidation of the metals in the hot liquid mixture.
B materials BAKELITE phenol-formaldehyde resin compounds	BAKELITE is a hard brittle plastic or thick resin made from phenol and formaldehyde (methanal). When solid it has a strong cross-linked polymer structure which is an excellent electrical insulator and quite heat resistance - its a thermosetting polymer.	Uses of bakelite: These phenol-formaldehyde plastics/resins have a wide rage of uses e.g. electrical fittings, saucepan handles, ... (but now replaced by PVC and poly(propene).
BAKING SODA	see SODIUM HYDROGENCARBONATE	Uses of baking soda: see SODIUM HYDROGENCARBONATE
BASES	Substances that react with acids, the neutralisation reaction producing salts. If soluble in water they are called alkalis.	Uses of bases: Need to look up individual bases/alkalis like ammonia, sodium hydroxide, calcium oxide etc.
BAUXITE	A mineral ore consisting mainly of aluminium oxide.	Uses of bauxite: One of the main ores for extracting the metal aluminium.
BIODEGRADABLE MATERIALS	A term, usually applied to waste materials, meaning that they will be naturally broken down by natural means so as not to leave a potential pollutant.	Uses of biodegradable fuels: Biodegradable plastic are being developed and technical progress seems good so far!
BIOFUELS	Biofuels are organic fuel molecules made from some naturally grown crop.	Uses of biofuels: e.g. sugar beet to produce sugar which is fermented into ethanol. Rape seed oil can be made into biodiesel for agricultural vehicles.
BRASS (alloy mixture) Cu + Zn atoms	A metal made from mixing copper and zinc. Copper is quite weak and zinc is brittle, but the mixture is quite strong and hard wearing.	Uses of brass: Brass has many uses e.g. wire, ammunition cartridge cases, tubing, casting decorative objects or plaques.
BROMINE Br₂ molecules and compounds	Bromine is a dark red low boiling point covalent liquid. It forms both ionic and covalent compounds.	Uses of bromine: The element is not used directly but is converted into important compounds. It is added to ethene to make (covalent) 1,2-dibromoethane which is used in manufacturing anti-knocking agents in motor fuels. Other organo-bromine compounds are used as flame-retardants which inhibit combustion if materials catch fire, to make fumigants in pest control and disinfectants. Silver bromide (ionic AgBr) is used in photography - the photographic film emulsion layer that reacts to light.
BRONZE	Alloy mixture of the metals copper and tin. The tin hardens and strengthens the relatively weak copper.	Uses of bronze: This strong hard wearing easily cast metal is used for cog wheels, ships propellers, statues, coins.
BUCKMINSTER FULLERENES	See CARBON	Uses of carbon: See CARBON See also Giant covalent structures and large organic molecules
BUTANE (compound) C₄H₁₀ molecules	A colourless pungent petrol like smelling hydrocarbon gas belonging to the homologous series of covalent organic molecules called alkanes.	Uses of butane: Liquified under pressure and stored in thick steel fuel gas tanks e.g. calor/bottled gas.
C materials CADMIUM (element) Cd atoms and compounds	CADMIUM is a white lustrous metal, moderately reactive to form salts with acids.	Uses of cadmium: Used in metal electroplating, alloyed with copper for tramway wires, some rechargeable batteries (NiCad cells). Cadmium compounds are used as pigments (cadmium sulphide CdS is yellow), plasticizers for plastics, phosphors in colour TV tubes.
CALCIUM (element) Ca atoms	A hard grey-white lustrous meal. Very reactive and rapidly dissolves in most acids forming salts. Because its high reactivity it will displace many other metals from their compounds.	Uses of calcium: Calcium is used to extract metals like thorium, vanadium and zirconium from there compounds by displacement reactions, a deoxidisers (e.g. it can be added to a molten metal mixture to remove traces of oxygen and it is used in alloys too. As its ion, Ca²⁺, it is an important dietary element for the body - calcium compounds are needed for the structure of bones and teeth.
CALCIUM CARBONATE (compound) CaCO₃, Ca²⁺CO₃^2-	An ionic white solid compound. Occurs naturally as the sedimentary rock limestone, which is an important raw material for both the construction and chemical industry. It is insoluble in water but dissolves in acids to form salts. It also occurs as the metamorphic rock marble which is much harder and less prone to weathering and can be polished to fine surface finish.	Uses of calcium carbonate : Uses of limestone: Used in the manufacture of iron & steel - slag removal, neutralise soil acidity, road making, stone block building material, making cement by roasting limestone with clay in a rotary kiln, blackboard chalk, heated in a kiln to make calcium oxide (lime, quicklime used to control excess acidity of agricultural land). Marble is used for building stones, flooring and statues, but much more expensive than limestone.
CALCIUM HYDROXIDE (compound) Ca(OH)₂	An ionic compound, a white powder that is slightly soluble in water to give an alkaline solution of ~pH 12. Its a base and neutralises acids forming calcium salts.	Uses of calcium hydroxide : Uses of slaked lime: When mixed with water it makes a white slurry used to 'whitewash' houses (quite an exothermic reaction). Use in agriculture to control soil acidity. Sometimes called 'slaked lime' because it is formed from calcium oxide ('lime') + water.
CALCIUM OXIDE (compound) CaO, Ca²⁺O^2-	A white high melting ionic solid which is slightly soluble in water to give an alkaline solution ~pH 12. It is a base and so will neutralise acids to form salts.	Uses of calcium oxide : Uses of lime : Uses of quicklime: It is used in steel making instead of limestone to remove the last silica and other mineral impurities as slag. It is known as lime/quicklime and is also used to control the acidity of soil when the pH is too low for good crop/plant growth.
CALCIUM SULPHATE CaSO₄, Ca²⁺SO₄^2-	A white ionic compound that is slightly soluble in water.	Uses of calcium sulfate: Plaster of Paris is made from calcium sulfate and water.
CARBOHYDRATES (organic compounds) e.g. sugars and starches.	Small to huge covalent molecules of carbon, hydrogen and oxygen. Most naturally occurring sugars contain 6 or 12 carbon atoms e.g. C₆H₁₂O₆ glucose/fructose C₁₂H₂₂O₁₁ sucrose (C₆H₁₀O₅)_n starches are natural polymers where n is a very large number of repeating units.	Uses of carbohydrates: Sugars are used in food preparation as a sweetening agent and provider of energy (high on calories) and starches like cornflower are used as thickening agents. For more details see individual substances e.g. glucose and Starch.
CARBON (element) C atoms Three allotropes, graphite, diamond, fullerenes, all solids.	(i) Coal: Mainly carbon from plant remains but contains small amounts of minerals and organic compounds. Coke is made by roasting coal at a high temperature which drives off organic tar, ammonia gas and water. (ii) Graphite: It has a porous structure so readily absorbs gases and certain dissolved compounds in solutions. Slippery black solid, high melting point, relatively good conductor of heat or electricity, doesn't dissolve in anything. Charcoal and coke have very porous graphitic structure. (iii) Diamond: A very hard and high melting colourless (usually) crystals. Refracts light strongly to give vivid 'sparkling rainbow colour' effects. (iv) Buckminster Fullerenes (bucky balls) and carbon nanotubes: Nanotubes are very strong and conduct electricity. Nanoparticles in general have different properties to the bulk material and their structures are manufactured by building them molecule-by-molecule or by 'stripping' a material down to nanoscale size and characteristics.	Uses of carbon in its many forms: (i) A high % of coal is carbon, an important fossil fuel. Anthracite is almost pure carbon and cleaner burning. Uses of coke: An important industrial and domestic solid fuel. It is the reducing agent (O remover) in the blast furnace for the conversion of iron oxides into iron and domestic fuel. (ii) Graphite is Electrodes in aluminium manufacture by electrolysis of aluminium oxide. Finely powdered charcoal, mainly graphite, is used for decolourising solutions and removing 'taste' and 'odours' in water purification and deodorising e.g. shoes! Graphite is used in 'lead' pencils and in lubricants, contact brushes in electric motors/dynamos. (iii) Diamonds are used in cutting tools, jewellery - lustrous, usually colourless?, but attractive sparkling effects in light. (iv) Buckminster Fullerenes 'bucky balls' can 'cage' other molecules and may be used in drug delivery systems, sun creams. Carbon nanostructures: Nanotubes are used as semiconductors in the electronic industry (part of an electrical circuit), sun creams, textiles, sports equipment e.g. reinforce graphite/carbon fibres in tennis rackets (strong and light), single crystal nanowires for computer processors, mobile phone batteries, catalysts attached to nanotubes which have a very large surface area (rates of reaction factor). More details on giant covalent structures, allotropes of carbon and large organic molecules
CARBON DIOXIDE (compound) CO₂ molecules	Small covalent molecule of carbon and oxygen. Colourless, odourless gas that doesn't support combustion. O=C=O is a slightly acidic gas when dissolved in water - moderately soluble.	Uses of carbon dioxide: Fire extinguishers, carbonated 'fizzy' drinks, dry ice (solid blocks at -78^oC).
CARBON MONOXIDE (compound) CO molecules	Small covalent molecule. Toxic colourless odourless gas.	Uses of carbon monoxide: Formed from coke in the blast furnace and acts as a reducing agent to free the iron from iron oxide ore. The excess can be burned as fuel. It is used in the synthesis of the alcohol methanol by combining it with hydrogen. CO + 2H₂ ==> CH₃OH
CARBOXYLIC ACIDS (compounds, 'fatty acids') contains -COOH group	Covalent molecules belonging to a homologous series of organic molecules.	Uses of carboxylic acids : Uses of fatty acids: Carboxylic acids have some direct uses but they are usually converted into a more useful chemical form e.g. they combine with alcohols to form esters used in perfumes-fragrances and food flavourings. The analgesic/pain killer aspirin is a carboxylic acid See GCSE Extra Organic Chemistry Notes
CATALYSTS (elements, compounds or mixtures)	A huge variety of substances and structures which speed up chemical reactions. They are obviously important from the chemical economics of industry to the functioning of our bodies.	Examples of uses of catalysts: Iron, Fe atoms, catalyses the combination of hydrogen and nitrogen to make ammonia. Vanadium pentoxide, V₂O₅ ionic compound, is used in the conversion of sulphur dioxide to sulphur trioxide in the manufacture of sulphuric acid. All enzymes are protein molecules and they control all the chemistry of living systems and are used for chemical synthesis in industry e.g. the fermentation of sugar to alcohol.
CAUSTIC SODA	see SODIUM HYDROXIDE	Uses of caustic soda: See SODIUM HYDROXIDE
CEMENT (mixture of compounds)	Made by heating limestone and clay at a high temperature in a rotary kiln. Chemically it is a mixture of calcium silicates and calcium aluminosilicates.	Uses of cement: ingredient in concrete, plaster (Portland cement) and mortar.
CERAMICS (mixtures of compounds)	They have giant covalent structure and are all high melting point, low thermal/electrical conductivity i.e. good heat/electrical insulators.	Ceramics covers a wide range of materials such as pottery, glasses, cement, concrete. Uses of ceramics: Pottery from pots to tiles, panes of glass, glass fibres, cement in concrete in the construction industry. Need to look up individual materials e.g.
CFCs CHLOROFLUOROCARBONS (compounds) e.g. CCl₃F, CCl₂FCClF₂ molecules in which all the H atoms of an alkane are replaced with Cl or F atoms	CFC chlorofluorocarbons - organic covalent molecules made of a combination of chlorine, fluorine and carbon atoms. They are colourless gases or low boiling point liquids. They are chemically quite stable, non-toxic and non-flammable i.e. quite safe to use (or so we thought!).	Uses of CFCs: Until recently they have been used extensively in refrigeration units, air conditioning units, bubbles in expanded plastics like polystyrene and insulating foams, the propellant gas in aerosols of deodorants, insecticides etc. They are good solvents for dry cleaning and cleaning grease off electrical equipment, but because of ozone layer destruction they are being replaced by HFCs and HCFCs.
CHLORINE (element) Cl₂ molecules and many chlorine compounds	Covalent diatomic molecules. Green gas, highly toxic and slightly soluble in water to give a weakly acid and strongly oxidising/bleaching solution. A very reactive element, readily combining with many metals and non-metals. Look up individual compounds like sodium chloride.	Uses of chlorine: PVC plastic manufacture, water sterilisation, chlorinated hydrocarbons (organo-chlorine compounds) are used as solvents, pesticides and disinfectants like TCP (trichlorophenol). It is combined with hydrogen to make hydrogen chloride which is dissolved in water to manufacture hydrochloric acid. Chlorine is used in the manufacture of household bleach, industrial bleaches for cotton, linen, wood pulp and domestic cleaners. Used in making CFCs and HCFCs.
CHLOROETHENE (compound) C₂H₃Cl, CH₂=CHCl	Small covalent gaseous unsaturated hydrocarbon molecule known as an alkene (C=C double bond). Colourless gas that can be polymerised to form poly(chloroethene) by virtue of having a double bond.	Uses of chloroethene: Polymerising to make poly(chloroethene) = PVC = polyvinyl chloride which is a very useful thermoplastic that is tough and a very good electrical insulator.
CITRIC ACID (organic compound) Contains three acidic -COOH carboxylic acid functional groups	A naturally occurring organic molecule classified as a carboxylic acid.	Uses of citric acid: Found in citrus fruits e.g. lemon juice. Used in sherbet powders with sodium hydrogencarbonate to make fizzy drinks - they react together to form carbon dioxide gas. Used in baking powders containing sodium hydrogencarbonate - they react together to form carbon dioxide gas which produces the rising action in the bread dough or cake mix etc.
COKE	See CARBON	Uses of coke: See CARBON
COLOURINGS compounds and mixtures of all sorts of materials	A huge variety of materials, often organic molecules, natural or manmade to bring colour to materials. See also DYES.	Examples of colourings: Tartrazine is used as an orange food colouring. Iron oxide as haematite is a red-brown pigment (was used by prehistoric man!). Synthetic colours are used to make textiles (clothing, curtains, carpets etc.) and plastic materials more attractive. Transitional metal oxides are used to colour ceramics from tiles to glass e.g. cobalt oxide to give the cobalt blue colour.
COMPOSITE MATERIALS (mixtures)	A wide variety of structures, but the idea is to combine different materials with different characteristics to produce a 'composite' with the desired properties for a particular purpose. Any component on its own would not meet the required specification.	Examples of uses of composite materials: glass fibre in reinforced plastic (boats, car bodies), reinforced glass (windows), reinforced concrete with steel rods (beams-bridges, buildings etc.), glass reinforced and bone, carbon fibres/nanotubes in sports equipment like clubs, racquets, bicycle frames and also in protective equipment like body armour (strong and light).
CONCRETE (mixture of compounds)	Prepared by mixing cement, sand, gravel and water. The mixture becomes hydrated and the components bond together to form a hard tough material we call concrete.	Uses of concrete: An important structural material for bridges and buildings etc. etc.
COPPER (element) Cu atoms	Quite a strong malleable metal with excellent thermal (heat) and electrical conduction properties.	Uses of copper: Copper wiring, alloyed with zinc to make brass, piping for plumbing e.g. central heating systems, hot water cylinders. Used in coinage - alloyed with nickel for coins,
COPPER(II) SULPHATE (compound) CuSO₄ or Cu²⁺SO₄^2-	An ionic compound of copper(II) and sulfate ions. Anhydrous copper sulphate is white, but you normally encounter it as the hydrated blue crystals containing water of crystallisation of formula CuSO₄.5H₂O which readily dissolves in water to give a blue solution.	Uses of copper(II) sulfate: Copper sulphate solution is the electrolyte in the purification of copper by electrolysis and in copper plating conducting objects (an example of the technique known as electroplating - see GCSE notes on the Extraction of Metals). Copper is a trace element in our/plants diet and copper sulfate is a soluble means of delivering it. Used as a wood preservative. Fungicide??
COSMETICS	See Fragrances and perfumes	Uses of cosmetics: See Fragrances and perfumes
COTTON	A natural organic polymer fibre.	Uses of cotton: Textile industry for sheets and clothing etc.
CRUDE OIL	See OIL	Uses of crude oil: See OIL
D materials DDT	DDT is a chlorinated aromatic organic compound that is soluble in organic solvents but not water. It is a harmful chemical which unfortunately is chemically very stable in the environment!	Uses of DDT: Used as a powerful insecticide e.g. mosquito control in countries where malaria is problem, but now banned in many countries because it builds up in food chains and affects the life of animals at or near the top of a food chain because it is stored in fatty tissues causing poisoning and genetic defects in offspring.
DETERGENTS (compounds) which are all surface active agents - so called 'surfactants'	Detergents are usually organic molecules with both a hydrophilic ('water liking') and a hydrophobic ('water hating') molecular groups. The hydrophilic group is a neutralised acidic group and is the smallest part of the molecule and strongly interacts with water. The much longer hydrocarbon chain (R in formulae below) interacts with water insoluble materials like fat/grease. Examples: The potassium salt of a long chain carboxylic 'fatty' acid or the sodium salt of a sulphonic acid. R-COO^-Na⁺ or R-OSO₂^-Na⁺	Uses of detergents: Detergents help remove dirt from the surface of materials in combination with water. They are described as surface active materials or surfactants. They help clean by lowering the surface tension of water so that it wets the surface more thoroughly, separating the grease and dirt from the surface and suspending the dirt in the water so it can be washed/rinsed away. There are two main types of detergent: Soap detergents ('soapy soaps') are made from reacting animal fats or vegetable oils with a strong base/alkali like sodium hydroxide or potassium hydroxide. Soapless detergents ('detergents') are made from hydrocarbon molecules from oil which can be reacted with concentrated sulphuric acid to make sulfonic acids. Washing powders or liquids are developed into complex formulations and may contain detergents, sequestering/complexing agents to soften hard water, enzymes to break down protein food/blood stains, optical brighteners to give fabrics a bright-white look, an oxygen bleach and finally a dash of perfume to give the washed clothes a distinctive and attractive 'freshness'.
DIAMOND	See CARBON	Uses of diamonds: CARBON
DISINFECTANTS (elements or compounds which act as sterilising agents)	Disinfectants are chemicals like chlorine, ozone, sodium chlorate(I) and are usually powerful oxidising agents. Nano sized particles of silver. They kill micro-organisms like harmful bacteria.	Uses of disinfectants: Chlorine/ozone used in water purification. Sodium chlorate(I) is used in toilet cleaning/bleaching agents. Sprays of nano sized particles of silver have powerful antiviral, anti-fungal and anti-bacterial action e.g. to sterilise an operating theatre. Unlike antiseptics, disinfectants cannot be used on the skin and any other living tissues because there chemical action is to strong for tissue you do not want to kill.
DNA (compound) Deoxyribonucleic acid.	Long organic molecules of repeating units of a combination of base on a sugar-phosphate backbone. Structurally it is described as a double helix of two polynucleotide chains. It carries the genetic code for the whole structure of an organism from a single self-reproducing cell to the most complex of multi-celled organisms.	Uses of DNA: DNA is used forensic analysis to identify individuals at a crime scene from traces of body tissue or fluid material. The manipulation of DNA is used in the very controversial subject of genetic engineering with its uses in medicine for identifying and treating potential health problems and in agriculture e.g. to develop GM crops resistant to pests.
DRUGS and MEDICINES (inorganic, and often organic compounds) The 'drug' is a specific molecule with a particular pharmacological action and a medicine is the complete formulation of the means of administering the drug to a patient i.e. the method of delivery.	A drug is an externally administered substance which modifies or affects chemical reactions in the body. They may alter incoming sensory sensations, alter mood or emotional state, alter physiological state, alter state of consciousness, activity level or coordination. Most of the medicines you take e.g. aspirin and other analgesics contain an active organic molecule. There are literally thousands of drugs-medicines on the market. See GCSE notes on Extra Organic Chemistry for the molecular structure of some analgesics.	A few of the thousands of uses of drugs and uses of medicines in the 21st century: Analgesics medicines are painkillers and reduce pain e.g. aspirin, ibuprofen, paracetamol, codeine. Powerful and dangerous pain killing drugs include morphine and molecules derived from heroin. Antibiotics like penicillin are responsible for saving millions of lives from various diseases by denaturing harmful bacteria cells. 'Milk of magnesia' to control excess stomach acidity causing indigestion 'heart burn'. There are many types or classes of drugs e.g. drugs which act on the central nervous system e.g. analgesics, sedatives, tranquilisers, hypnotics, antidepressants, narcotics, anaesthetics. Drugs which kill bacteria like antibiotics and sulfonamides (sulphonamides), anti-cancer drugs are used in chemotherapy ('chemo') like cis-platin, anti-viral drugs help fight HIV infections, cardiovascular drugs to control blood pressure e.g. lower it, control or stimulate heart beat. Anti-inflammatory drugs suppress the bodies immune system if it overacts to some perceived threat. Drugs used to help maintain a healthy digestion system e.g. antacids, laxatives and drugs to treat ulcers in the stomach and intestines. We have a lot to thank chemistry for providing these treatments, there are always but as ever, with human ingenuity and application of scientific knowledge, there is plenty of scope for self-abuse, excessive profiteering by multi-international drug companies etc.
DYES - DYESTUFFS (compounds)	The original dyes came from plant or animal materials e.g. blue woad, orange-red alizarin and indigo blue from plants and red cochineal from dried insects. These days (in fact from the late 19th century onwards) most dyestuffs are synthesised organic molecules like the azo dyes.	Uses of dyes: Synthetic dyestuffs are used for dyeing fabrics and colouring plastics. Apart from natural wood and stone (not stained/painted) just about everything else around you in the home is coloured with something or other and much of processed food too! - just check out the E numbers!
E materials ELECTROLYTES (compound or mixture)	Electrolytes are any aqueous (water) solution or molten material containing ions which are free to move and carry an electric current e.g. sodium chloride solution (Na⁺_(aq) and Cl^-_(aq) ions) or molten aluminium oxide (Al³⁺ and O^2- ions).	Uses of electrolytes: Industrial uses include all electrolysis processes like aluminium extraction from molten aluminium oxide (purified bauxite ore), purifying copper using copper electrodes and copper(II) sulphate solution. Revision notes on the Extraction of Metals Electrolytes are used in fuel cells, zinc-carbon batteries (ionic ammonium chloride paste) and sulphuric acid is used in lead-acid batteries, so all battery/cell systems need an electrolyte. For living systems, healthy cell activity requires the presence of certain ions both inorganic and organic e.g. the nervous system works via electrical impulses transmitted by the movement of ions, so sodium, chloride, potassium other ions are needed for this purpose in our diet.
EMULSIFIERS (usually mixtures of organic compounds from natural or man-made sources)	An emulsion is usually one liquid/solid dispersed (but NOT dissolved) in another liquid (often water) and an emulsifying agent inhibits the separation of the two main components. Emulsifying agents are surfactant molecules having a 'water loving head' part (hydrophilic) and 'water hating tail' part (hydrophobic) groups in the same molecule i.e. they can interact with different immiscible liquids like oil and water.	Uses of emulsifiers and emulsifying agents: Emulsion paints can be oil or water based and the pigment dispersed in the mixture too. Lecithin, alginates and mustard, egg yolk etc. are used as emulsifying agents in foods. Salad dressings (based on olive oil plus vinegar) and mayonnaise (stabilised with egg yolk) are emulsions but may need a good shake before use! Creamy foods, cosmetic foundation creams and brushless shaving creams are oil-in-water emulsions, cold creams and cleansing creams are water-in-oil emulsions and all of these need an emulsifier to stop the components of the mixture separating out.
ENZYMES (very complex compounds) Thousands of different organic compounds made of combinations of C, H, O, N, often a metal atom like Fe, Cu or Mg etc. and usually over a 1000 atoms in the molecule.	These are complex protein molecules that function as highly specific and sophisticated chemical biological catalysts, all extracted plant or animal sources. There are thousands of them and essential to the life of every cell in every organism as they control most of the chemical reactions throughout the structure of an organism. Without these catalyst the chemistry of life would be too slow to continue! The names of enzymes end in ...ase e.g. amylase, protease, invertase, isomerase etc.	Uses of enzymes: Enzymes from yeast extract are used in the brewing industry to convert sugars into ethanol, 'alcohol' for the drinks industry, or sugar cane into ethanol for biofuels. Some washing powders contain proteases which are enzyme that break down proteins such blood or egg yolk stains on clothes. Proteases break down proteins and are used to 'pre-digest' the protein in some baby foods. Carbohydrases are used to convert starch syrup into sugar syrup. Invertase is used to make the sugar for soft chocolates. Isomerase is used to convert glucose syrup into fructose syrup, which is much sweeter and therefore can be used in smaller quantities e.g. in slimming foods. Pectinase breaks down insoluble pectin polysaccharides and so is used in clarify fruit juices. Amylases break down carbohydrates and Lipases break down fats. Enzymes are used in genetic engineering and penicillin production. The dairy industry uses enzymes made by microorganisms (bacteria) to produce yoghurt and cheese from milk. The bacteria enzymes convert the sugar in milk (lactose) into lactic acid. Some revision notes on enzymes
EPOXY RESIN Organic compounds - macromolecules or polymers	Polyethers (have a C-O-C linkage) formed by condensing together e.g. 3-chloro-1,2-epoxypropane ('epichlorhydrin') with polyols like bisphenol. The polyethers need a curing agent to convert them to resins. The resins are thermosetting to tough adhesive materials which are chemically resistant and electrical insulating.	Uses of epoxy resins: They are used as adhesives, coatings and in composite materials.
ESTERS organic compounds synthesised by reactions such as: carboxylic acid + alcohol ==> ester + water	Esters form a homologous series in organic chemistry and prepared by reaction of a carboxylic acid (or derivative) and an alcohol. R-COO-R' where R- = H-, alkyl e.g. CH₃-, CH₂CH₃- or aryl e.g. C₆H₅- etc. -R' = alkyl e.g. CH₃-, CH₂CH₃- or aryl e.g. C₆H₅- etc. Pleasant smelling, often with a sweetish odour, colourless liquids and generally harmless chemicals.	Uses of esters: Esters are found naturally in fruits () but they are now synthetically manufactured on an industrial scale. They are used in the cosmetics industry e.g. perfumes-fragrances, enhancing the smell of household products, 'air fresheners', food additives e.g. fruit flavourings. They are also useful organic solvents because they dissolve a wide range of compounds and they are used as plasticisers to make polymers more 'plastic'. Some drugs like aspirin are esters and the insecticides malathion and pyrethrin are also esters. () Ethyl butanoate has the odour of pineapple and 3-methylbutylethanoate gives pear drop sweets their taste and smell. Oils like olive oil, palm oil etc. are esters of an alcohol called glycerol. When heated with sodium/potassium hydroxide they form salts. These are sodium/potassium salts of long chain fatty acids and are used as soaps.
ETHANE (compound) C₂H₆ or CH₃CH₃	A colourless hydrocarbon gas belonging to the homologous series of covalent organic molecules called alkanes.	Uses of ethane: It readily burns and so is used as a fuel gas. It can be cracked to make the more useful ethene. It is used in very low temperature refrigeration units but is flammable/explosive with air.
ETHANOIC ACID (compound) CH₃COOH	Small covalent organic molecule, strong smelling colourless liquid when pure. It belongs to the homologous series of organic molecules called carboxylic acids.	Uses of ethanoic acid (uses of 'acetic acid'): Old name acetic acid, used in the food industry and food preparation e.g. vinegar, pickling vegetables and eggs. It combines with alcohols to make ... ethanoate esters ('acetates') e.g. ethyl ethanoate. Ethanoate esters are used as solvents and in the perfumery-cosmetics/food industry as fragrances/flavourings. It can be converted to ethanoic anhydride which is used to manufacture cellulose ethanoate used for artificial fibres in the textile industry.
ETHANOL (organic compound) CH₃CH₂OH	Small covalent molecule, an organic compound of C, H and O atoms belonging to the homologous series of similar molecules called alcohols. Highly toxic colourless liquid. In aqueous solution, the more concentrated - the more dangerous!	Uses of ethanol ('ethyl alcohol'): Ethanol is used in alcoholic drinks and beverages, a solvent, a fuel e.g. methylated spirits in a camping cooker and as a biofuel from fermented sugar cane or sugar beet, the ethanol ('alcohol') is distilled off and it can be blended with petrol. Ethanol is used to manufacture ethyl .. esters used in the perfumery-cosmetics/food industry as fragrances/flavourings. Ethanol is the starting point for the manufacture of other organic chemicals e.g. oxidised to ethanal ('acetaldehyde') or ethanoic acid ('acetic acid') which in term are converted to other useful products.
ETHENE (organic compound) C₂H₄ or CH₂=CH₂	An unsaturated (C=C bond) organic covalent molecule belonging to the homologous series of hydrocarbons called alkenes. Its a colourless smelly gas.	Uses of ethene: It doesn't really have any uses as ethene itself BUT it is as the starting molecule in the manufacture of a wide range of products. It is readily polymerised to make the plastic ploy(ethene) - 'polythene'. It can be reacted with water to make ethanol,
F materials FABRICS (compounds/mixtures)	Fabric is a general term for materials used in the clothing or furniture industry	Uses of fabrics: Clothing, textile and furniture industry.
FATS (organic compounds)	Saturated esters of glycerol and long chain fatty/carboxylic acids.	Uses of fats: Hydrogenated fats like margarine used in the food industry and in the home.
FATTY ACIDS	See CARBOXYLIC ACIDS	Uses of fatty acids: See CARBOXYLIC ACIDS
FERTILISERS (compounds and mixtures)	See AMMONIA and PHOSPHORUS Mixtures of ammonium salts, nitrate salts, potassium salts and phosphate salts	Uses of fertilisers: Added to land to promote plant growth and increase yields of crops etc. The three most important elements in the mixture of compounds of a fertiliser are nitrogen, phosphorus and potassium, so fertilisers are often classified by their N P K values.
FIBRE - dietary - large organic molecules in food of plant origin	Dietary fibre is can be defined as non-starch polysaccharides, though plant fibre can be defined as food components resisting digestion in the small intestine. Whatever, they are large naturally occurring polymeric organic molecules of C, H and O atoms.	Uses of dietary fibre: Important component in a healthy diet and aid food digestion and the smooth functioning of the whole of the digestive track. They are found in plant materials from fruit, grains and vegetables etc. Fibre is added to many breakfast cereals and is automatically present in wholemeal bread.
FIBRES - natural or man-made material (not for food!)	Apart from carbon fibres and glass fibres, they are usually long chain organic polymer molecules. Each fibre is relatively high tensile strength and when produced is thicker thread or a bulk composite format, you have a strong and useful material.	Uses of fibres: Wide range of materials, including composites, with a wide range of uses e.g. glass fibres in insulation and fibre optics, carbon fibre composites in sports equipment, Nylon and Terylene fibres in the clothing-textile industry.
FLAVOURINGS-FLAVOUR ENHANCERS (compounds-mixtures)	Usually salt (sodium/potassium chloride, NaCl/KCl), organic molecules like esters and other organic compound/mixtures from plant or animal extracts which are now widely synthesised to 'mimic nature'. See ESTERS	Uses of flavourings: To enhance the appeal of food. Monosodium glutamate is added to a huge range of foods. See ESTERS for more examples.
FLUORINE (element) F₂ molecules, but only used in compound form e.g. combined with metals as a fluoride salts or combined with non-metals e.g. organic fluorine compounds.	Fluorine forms ionic salts with metals e.g. potassium fluoride, KCl or K⁺F^-, which is a high melting colourless crystalline solid soluble in water. Fluorine, like chlorine, can replace hydrogen in alkanes to form organo-fluorine compounds. These are covalent molecules, low boiling colourless	Uses of fluorine: Fluorine is too reactive and highly toxic for any direct uses so it is used to manufacture other useful fluorine compounds e.g. it is used in making CFCs, HFCs and HCFCs for refrigeration units and the gas in aerosol sprays. CFCs are being replaced by HFCs because as upper atmosphere 'pollutant' they cause destruction of the uv protection ozone layer. Fluoride salts can be added to domestic water supplies i.e. tap water and toothpaste since it is believed to improve dental health e.g. stronger enamel and less tooth decay - but fluorides are potentially harmful and so the treatment is controversial.
FOSSIL FUELS (mixture)	See CARBON and OIL	Uses of fossil fuels: Coal, coke (made by heating coal), anthracite, lignite, peat and oil products are all burned to release heat energy.
FRAGRANCES - PERFUMES	See ESTERS	Uses of fragrances and perfumes: See ESTERS
Fullerenes	See CARBON	Uses of fullerenes: e.g. Buckminster Fullerenes see CARBON
FUNGICIDES	They can have a huge range of chemical structures but they are often compounds of sulphur, tin, mercury, nickel and copper.	Uses of fungicides: Fungicides inhibit fungal growth which attacks wood or plastic surfaces etc.
G materials GLASS is a fused mixture made from heating together sand, sodium carbonate and lime/limestone. The proportions can be varied and metal and non-metal oxides added to produce specialised glasses.	Glass is a curious substance! Technically it is a supercooled liquid forming a transparent non-crystalline solid with a giant covalent structure. It is relatively high melting and a very poor conductor of heat and electricity i.e. a good insulator. It is chemically resistant to chemical attack and is effectively an insoluble substance.	Uses of glass: Glass is extensively used for window panes, laboratory glassware, decorative objects ('glass-china'). Glass fibres, thin filaments of glass, are combined with resins to produce composite materials for 'fibre-glass' boat hulls and car bodies. Glass fibres are used in optical systems in medicine for internal body examinations and decorative displays in the home. Soda glass is cheap but more expensive heat resistant glasses e.g. Pyrex are used for cooking bowls and laboratory apparatus.
GLUCOSE (compound) C₆H₁₂O₆ molecules	A covalently bonded organic molecule and a member of the carbohydrate family of sugars.	Uses of glucose: It is widely used in the confectionery and food industry e.g. sweetener in food, chocolate etc. It can be fermented by yeast to make ethanol. It is the sugar of the blood system and so is added to high energy drinks to provide a rapid and easily digested source of energy.
GOLD (element) Au atoms and gold salts/complex ion compounds.	Gold has the typical properties of a metal e.g. good electrical conductivity, high melting point, malleable etc., except it is yellowish in colour and apart from copper, all the other metals are white-silver-silvery grey. It is a very unreactive metal.	Uses of gold: Gold bars are used in monetary systems, jewellery because of its attractive untarnished look, an infra-red surface reflector, electrical contacts, tooth fillings. Its compounds are used in the treatment of rheumatoid arthritis.
GORETEX Gore-Tex is a composite mixture of several compounds	Goretex consists of nylon laminated with a poly(tetrafluoroethene)/PTFE or polyurethane membrane. So it is a composite mixture of polymers.	Uses of goretex: Waterproof fabrics with breathability e.g. anoraks and other sports/outdoor activities gear. The holes in the PTFE/polyurethane membrane are too small to let liquid water through but big enough for the vapour of individual water molecules to pass through ('breathable'). A PTFE/polyurethane laminate is not strong enough on its own so it needs the nylon base too.
GRANITE	An igneous rock consisting of a mixture of silica based minerals formed from the slow cooling of magma/lava in the earth's crust.	Uses of granite: A fine and expensive building stone which is highly resistant to weathering - unlike limestone!
GRAPHITE	see CARBON	Uses of graphite: see CARBON
H materials HAEMATITE	See IRON OXIDES	Uses of haematite: A principal ore for the extraction of iron.
HALOGENS (elements) e.g. Cl₂, Br₂, I₂ molecules	Group 7 elements of the periodic table. Group 7 The Halogens GCSE Revision Notes	Uses of halogens: Best to look up individual elements and their compounds e.g. fluorine compounds, chlorine, sodium chloride and iodine,
HCFCs HYDROCHLOROFLUOROCARBONS and HYDROFLUOROCARBONS HFCs (compounds) e.g. CH₃CCl₂F and CH₂FCF₃	HCFC Hydrochlorofluorocarbons (combination of H, Cl, F and C atoms) and HFC hydrofluorocarbons (combination of H, F and C atoms). These are organic compounds produced from alkanes by replacing some of the hydrogen atoms with chlorine or fluorine atoms.	Uses of HCFCs and uses of HFCs: Until recently they have been used extensively in refrigeration units, air conditioning units, bubbles in expanded plastics like polystyrene and insulating foams, the propellant gas in aerosols of deodorants, insecticides etc. They are good solvents for dry cleaning and cleaning grease off electrical equipment, but because of ozone layer destruction they are the use of CFCs.
HELIUM (element) He atoms	Colourless chemically unreactive gas ('inert') belong to the 'Noble Gases' Group 0 of the Periodic Table. Its density is much less than air.	Uses of helium: Balloons (much safer than explosive hydrogen), oxygen-helium breathing mixtures for divers.
HERBICIDES (compounds acting as weed killers)	They have a range of chemical structures, though most are synthetic organic compounds.	Uses of herbicides: Herbicides are basically weedkillers or growth regulators and are usually selective in their effect on plants.
HYDROCARBONS (compounds) C_xH_y, huge range of the values of x and y e.g. butane C₄H₁₀, ethene C₂H₄, benzene C₆H₆ etc.	Covalent molecule organic compounds made up of combinations of carbon and hydrogen. They form several homologous series e.g. the saturated alkanes like butane, unsaturated alkenes like ethene and aromatic compounds based on benzene.	Uses of hydrocarbons: Alkanes are used as fuels but they, along with alkenes and aromatics form the starter molecules to make a wide range of useful products, so need to look up individual compounds like methane, ethene, propane or butane and the homologous series of alkanes or alkenes to which they belong.
HYDROCHLORIC ACID (compound) HCl_(aq) aqueous solution	A strong mineral acid solution of hydrogen ions, H⁺ or H₃O⁺ and chloride ions, Cl^-. It is manufactured by dissolving the gas hydrogen chloride in water.	Uses of hydrochloric acid: Widely used in the chemical industry. Reacts with bases to form chloride salts. Its a catalyst for hydrolysing sugar cane to glucose.
HYDROGELS	see POLYMER GELS	Uses of hydrogels: see POLYMER GELS
HYDROGEN (element) H₂ molecules	Colourless gas, very flammable and explosive if ignited in air.	Uses of hydrogen: rocket fuel (mixed with an oxidant - oxygen supplier), meteorological balloons (cheaper than helium), potential to be a clean fuel if it can be economically produced on a large scale - on combustion just burns to form 'non-polluting' water only, fuel cells, hydrogenation of unsaturated vegetable oils to make 'solid' margarine. Combined with chlorine to form hydrogen chloride which is dissolved in water to make hydrochloric acid.
HYDROGEN CHLORIDE HCl molecules	Colourless, choking, acidic corrosive gas.	Uses of hydrogen chloride: It is dissolved in water to make hydrochloric acid and is used in the manufacture of organo-chlorine compounds.
I materials IODINE (element) I₂ molecules and ionic compounds	IODINE is a diatomic covalent molecule. It is an almost black solid that readily sublimes on gentle heating to give a brilliant purple vapour. It is virtually insoluble in water but does dissolve in ethanol (alcohol) and potassium iodide solution.	Uses of iodine: Iodine solution is an antiseptic to sterilise wounds ('tincture of iodine'), silver iodide (AgI) is used in photography in the 'old fashioned' light sensitive emulsion film format.
ION EXCHANGE RESINS/MINERALS - usually complex naturally occurring minerals or synthetic polymers.	Ion exchange materials can be naturally occurring minerals or synthetic polymers. Within their structure they have either, immobile positive cationic groups that can weakly hold onto negative anions from a surrounding solution, or, immobile negative anionic groups that can weakly hold onto positive cations from a surrounding solution (usually aqueous media). In the process of adsorption on the material, one ion is exchanged for another.	Uses of ion exchange resins which are held in a column and the aqueous solution passed through: They can soften water by removing calcium and magnesium ions from the water so a scum does not form with soap. Using a mixture of a cationic and anionic ion exchange materials you can deionise water to make pure water (well at least remove all ions, any non-ionic impurity molecules will not be removed). Examples off ion exchangers include naturally occurring zeolite minerals and permutit is synthetic zeolite used to soften water by exchanging sodium ions on the permutit for calcium ions from the tap water (sodium ions do not form a scum with soap). Some washing powders contain permutit powder.
IRON (element) Fe atoms and STEEL ALLOYS - mixture of Fe atoms plus carbon and other metals and non-metals	Iron is a typical metal, high melting, strong and malleable (particularly when alloyed with other elements) and a good conductor of heat. Metal structure & properties notes	Uses of iron and uses of steel alloys: Iron is made into the alloy steel by mixing it with carbon and other metals like nickel, chromium etc. It can be used directly for cast iron objects. Iron and steel have a huge range of uses e.g. car bodies, cookers, nails, iron catalyst ammonia manufacture, cast iron gates, important element for living systems e.g. iron ions in haemoglobin molecules in red blood cells for respiration. Mild steel - car bodies, machinery. Stainless steel (alloy with chromium) - cutlery, surgical instruments, chemical plant reactor vessels.
IRON OXIDES (compounds)	Found naturally as Fe₂O₃ iron(III) oxide, haematite ore and Fe₃O₄ magnetite ore.	Uses of iron oxides: Both haematite and magnetite are important mineral ores used as source for extracting iron. Revision notes on the Extraction of Metals
K materials KEVLAR	Kevlar is a very strong, flexible and fire resistant polymer. It is a aromatic polyamide and the rigid linear polymer chains line up to form strong 2D sheets which strongly adhere to each other at the molecular level. It is much less dense than metals so has a much higher strength/weight ratio compared to e.g. steel.	Uses of Kevlar: Bullet proof vests form a strong protective layer. Bicycle tyre composites containing Kevlar are less likely to puncture. Kevlar 'rope' is much stronger than the equivalent weight of steel so it can be used to reinforce car tyres instead of steel wire.
L materials LEAD (element) Pb atoms and lead compounds	LEAD is very malleable and relatively unreactive metal, typical metallic properties, though too soft for most structural purposes	Uses of lead: Lead roofing, electrodes in lead-acid batteries, the alloy solder used for making electrical connections in circuits. Lead compounds are used as 'ant-knock' agents in petrol (being reduced as leaded petrol replaced by less polluting unleaded petrol), red lead is used in
LEATHER	Tough hard wearing fabric material made from cows skin.	Uses of leather: Clothing and furniture industry competing with cheaper PVC 'artificial leather' materials.
LIME