List of Important elements and terms related to Chemistry (science) with it’s definition and explanation.
• Acids: These are the chemicals that produce positively charged hydrogen ions (H+) or a proton in solutions.
• Adhesive: A substance that sticks two surfaces together.
• Aerated: Water that has had air (oxygen) blown through it.
• Aerosol: Very small solid particles suspended in air.
• Air pollution: Contamination of the atmosphere caused by the discharge, accidental or deliberate, of a wide range
of toxic substances.
• Alkali: A base which is soluble in water.
• Alloy: It is metal prepared by adding other metals or non-metals to obtain desired properties.
• Amino acids: The organic acids which are constituents of all proteins in living organism.
• Ammonium chloride: It is a white, soluble, crystalline salt, used in dry cells.
• Ammonium nitrate: It is a colourless, crystalline salt, used in some explosives.
• Antacids: Substances used to reduce the pH of stomach juices and, therefore, relive indigestion.
• Anodizing: It is a process of coating aluminium oxide, or alumina, using electrolysis, it makes the surface more
resistance to corrosion.
• Antibiotic: These are medicinal compounds producedsd by moulds and bacteria, capable of destroying or
preventing the growth of bacteria in animal system.
• Antiseptic: It prevents infections, decay and inhibits the action of microorganism.
• Aromatic compounds: These are organic compounds like benzene which have a strong smell
• Argon: It is a colourless gas which has no smell.
• Arsenic: It is poisonous metallic element.
• Asbestos: It is a useful variety of a rock-forming mineral which is fibrous, very heat-resistant and chemically inert.
• Asphalt: It is a brown or black tar-like substance, a variety of bitumen, found in a natural state or obtained by
evaporating petroleum.
• Aspirin: It is an acetyl salicylic acid.
• Bactericide: It is a substance used to kill bacteria e.g. antibiotics, antiseptics and disinfectant.
• Bath salts: These are salts used to soften hard water.
• Bauxite: The principal ore of aluminium, consisting of a mixture of hydrated aluminium oxides and hydroxides,
generally contaminated with compounds of iron, which gives it a red colour.
• Beta Particle: Electron ejected with great velocity from a radioactive atom that is undergoing spontaneous
disintegration.
• Biodegradable: Capable of being broken down by living organisms, principally bacteria and fungi.
• Bitumen: It is a dark black viscous hydrocarbon manufactured artificially by heating coal, it is used in coating the
surfaces of roads.
• Blast furnace: It is a special kind of furnace, iron is made inside a blast furnace.
• Borax: It is a white crystalline salt with an alkaline nature used in the manufacture of glass, soldering of metals,
enamels, gems, soaps, etc.
• Boric acid: It is a white crystalline solid which behaves as a weak acid and used as mild antiseptic and in the
manufacture of cement, enamels, etc.
• Carbohydrates: Energy-producing organic compounds, e.g. cane sugar, glucose, starch, etc.
• Carbon dioxide: It is a colourless, odourless, tasteless gas about one and a half times as heavy as air. It is given
out during respiration.
• Carbon monoxide: It is a colourless, odourless gas resulting from the incomplete oxidation of carbon, it is
poisonous to animal for it bind to haemoglobin more strongly than oxygen.
• Carvacrol: A thick oil extracted from the oil of mint and used as an antiseptic and anaesthetic.
• Catalysis: A phenomenon in which the addition of a small quantity of a substance enhances the rate of reaction
manifold, without the added substance itself being consumed in the course of the reaction.
• Centrifuge: An apparatus that rotates containers at high speeds, creating centrifugal forces.
• Chemotherapy: It is the treatment of diseased by the administration of chemicals.
• Chlorine: It is a chemical element, a yellow, poisonous gas which dissolves in water. It makes water safe to drink.
• Chloroform: It is a sweetish, colourless liquids and used as a solvent and anaesthetic.
• Chlorophyll: It is a green pigment found in all members of the plant species, excluding fungi.
• Cholesterol: It is steroid compound in all animals, but not in plants.
• Charcoal: It is a black solid which contains carbon, it is made by heating wood in a closed space with no air.
• Cobalt: It is a very hard and silvery metal, it is mixed with iron to make cobalt steel.
• Chemistry: It is the science concerned with composition of matter and of the changes that take place in it under
certain condition.
• Chlorination: The addition of chlorine to drinking water and to water used in swimming pools in order to kill
dangerous bacteria.
• Citric acid: A colourless substance especially used in jams and fruit juices as a preservative.
• Coke: Light type of coal obtained when coal is heated in the presence of air.
• Corrosion: It is a process whereby stone or metal is chemically eaten away.
• Dichloro diphenyl trichloroethane (D.D.T.): It is a common insecticide insoluble in water, easily soluble in ethanol
and acetone.
• Dehydration: Elimination of water
• Desalination: The process of removing dissolved salts, mainly sodium chloride, from seawater and brackish water
to yield potable water for human consumption.
• Detergent: A synthetic cleaning agent, it has the ability to emulsify oils and remove dirt.
• Diamond: Hardest substance known, made of pure carbon.
• Distilliation: A process involving both evaporation and condensation simultaneously, used for purifying liquids.
• Dynamite: It is used for blasting. It contains sodium or ammonium nitrate sensitized with nitroglycerine and use
absorbers like wood pulp.
• Electroplating: A method of coating one metal with a thin layer of another metal.
• Emerald: The green germ variety of beryl: One of the most highly prized gemstones.
• Enamel: A hard material containing over 90 percent calcium and magnesium salts which provides protection
against corrosion or decay.
• Enzymes: Proteins that carry out different metabolic and functional reaction in animals and plants.
• Ephedrine: A white solid used in medicine for the treatment of asthma colds.
• Epsom salts: Hydrates of magnesium sulphate used in medicines to empty bowels.
• Ethylene: A colourless gas used in making plastic (polythene) and in artificial ripening of fruits.
• Ethanol: A colourless, flammable alcohol whose boiling point is 780 C. Ethanol is the alcohol contained in alcohol
drinks.
• Ether: It is colourless liquid which burs very easily, it evaporates very quickly.
• Evaporation: Conversion of a liquid into vapour without necessarily reaching the boiling point.
• Fermentation: A chemical change brought about in organic substance by the enzymatic action of living organism
such as yeast and bacteria.
• Ferrous: It describes iron or any metal which contains iron.
• Flash point: The lowest temperature at which a substance catches fire on being lighted with a flame.
• Flint glass: Glass containing lead silicate used for optical purposes.
• Fluoride: It is a chemical compound.
• Fluorescence: Emission of light by a substance when some radiations fall on it.
• Forging: A process in which metals are given the required shape by compressing them.
• Free radical: Group of atoms in particular combinations capable of free existence under special condition, usually
for very short periods.
• Hard water: Water that does not lather easily with soap, and that produces ‘fur’ or scale’ in kettles, it is caused by
the presence of certain salts of calcium and magnesium.
• Helium: It is colourless, odourless, gaseous, non-metallic element.
• Hormones: Compounds internally secreted in animal which stimulated organs in their respective action. e.g.
insulin, adrenaline, testosterone, etc.
• Hydrogen: It is colourless, odourless, gaseous, non-metallic element.
• Inert: It is a substance which does not burn and does not change when it is heated.
• Inorganic chemistry: It is branch of chemistry dealing with the element and their compounds, excluding the more
complex carbon compounds.
• Kinetics: It is the branch of chemistry that investigates the rates of chemical reactions.
• Krypton: It is colourless, odourless, gaseous, non-metallic element.
• Lactose: A sugar found in milk and used in some baby foods.
• Lignite: A soft, brownish-black coal in which the texture of original wood can still be seen.
• Lipids: Fats and their derivatives that occur in living systems.
• Litmus: It is a coloured dye which is often used to coat special strips of paper called litmus paper.
• Luminous: It describes something that gives out light.
• Lysergic Acid Diethylamide (LSD): It is an extremely powerful drug that causes distortions in thinking and feeling.
• Magnesia: A white, tasteless powder used as a mild laxative and antacid.
• Marsh gas: Consisting mostly of methane.
• Menthol: A white, waxy, crystalline solid obtained from the oil of pepper mints and used in medicine and
perfumery.
• Mercury: A silvery white liquid metal.
• Methane: It is a colourless gas.
• Methanol: It is also called methyl alcohol or wood spirit.
• Minerals: Ali compounds that are obtained from the earth’s crust.
• Milk of Magnesia: Common name for a suspension of magnesium hydroxide in water. It is a common antacid.
• Morphine: A pain killing drug, It is the main alkaloid present in opium, being 10 percent of its weight.
• Morter: A mixture of cement, sand and water used to bind together bricks and stones.
• Molten: State of a solid that has been heated until it melts.
• Mustard gas: A highly poisonous liquid which vaporises easily and is sued in chemical warfare.
• Napalm: An abbreviated form of sodium (Na) palmitate. It is a gel made up of some readily burning hydrocarbon
oils and soap. It is used a sin incendiary weapon with wide destructive power as it sticks to the target while
burning.
• Naphtha: It is a mixture of hydrocarbon of low molecular weight obtained either from coal tar, petroleum or shale
oil.
• Narcotic: It is a drug which tends to induce sleep or unconsciousness, for example, morphine.
• Neon: It is a chemical element and is a colourless gas which does not dissolve in water.
• Nerve Gas: It is a gas used in chemical warfare which is especially damaging to the nervous and respiratory
systems.
• Neutron: It is an elementary particle that is a part of the atoms of all elements except normal hydrogen. It is
present in the nucleus of the hydrogen. It is present in the nucleus of the atom along with another particle,
Proton.
• Nicotine: A poisonous oily liquid which is the principle compound in tobacco.
• Nitrates: Salts of metals, formed with nitric acid.
• Nitric acid: A strong minerals acid used in medicinal preparations and in industry.
• Nitrogen: A gaseous chemical element.
• Nobel metals: Metals such as gold, silver and platinum which are chemically much less reactive compared to
other metals.
• Non-ferrous metals: Any metal other than iron of steel.
• Nucleus: The central dense part of an atom which contains practically all its mass.
• Octane Number: A measure of the quality of petrol.
• Ore: A natural occurring mineral normally mined for the extraction of metal on a commercial scale.
• Organic Chemistry: Branch of chemistry that deals with carbon compounds,, in particular the more complex ones.
• Osmosis: The movement of solvent (liquid) through a semipermeable membrane separating solutions of different
concentrations.
• Oxidation: It is a kind of chemical reaction.
• Oxide: A compound of oxygen and another element,, frequently produced by burning the element or a compound
of it in air on oxygen.
• Oxygen: A colourless, odourless, tasteless, non-metallic, gaseous element.
• Ozone: A highly reactive pale-blue gas with a penetrating odour.
• Paraffin: It is an oily liquid.
• Pasteurization: A heat-treatment process to reduce the number of micro-organism present in food in order to
extend its shelf-life.
• Penicillin: An antibiotric produced by the fungus.
• Phosphorus: A highly reactive, non-metallic element.
• Photosynthesis: A process by which green plants trap light energy and use it to drive a series of chemical
reactions, leading to the formation of carbohydrates.
• Pig iron or cast iron: The crude, unrefined form of iron produced in a blast furnace.
• Pigment: It is a kind of coloured powder, It is mixed with liquids make paint.
• Pipette: Device for the accurate measurement of a known volume of liquid, usually for transfer from one container
to another, used in Chemistry and Biology laboratories.
• Plaster of Paris: A form of calcium sulphate, obtained from gypsum, mixed with water for making casts and
moulds.
• Platinum: A heavy, soft, silver-white, malleable and ductile, metallic element.
• Potassium: It is chemical element.
• Protein: Any of a large number of complex organic compounds made up of long chains of amino acids and found
in all living organism.
• Propene: A colourless, inflammable gas, it is widely used by industry to make organic chemicals, including polypropylene
plastics.
• Quicksilver: Another name given to mercury.
• Radiotherapy: It is used by doctors to help some of their patients.
• Radium: Radioactive, metallic element.
• Roentgen: It is a unit for measuring the dose of radiation.
• Saccharin: A white crystalline solid which is 550 times sweeter than sugar, but does not have any food value.
• Sapphire: Any gem, other than ruby, especially of blue colour due to traces of cobalt present in it.
• Sewage treatment: Waste water from industry or the home is treated in several ways in order to make it fit again
for use.
• Silica: A hard, insoluble white, colourless solid with a very high melting point.
• Silicon: It is the chemical element.
• Slag: It is the molten mass of impurities that is produced in the smelting or refining of metals.
• Smelting: A method by which metals are separated from their original ore.
• Smog: A form of air pollution, dark, thick dust laden sulphurous fog that pollutes the atmosphere in industrial
cities.
• Sponge Iron: It is iron in porous form.
• Sodium: It is chemical element.
• Soft water: Type of water that easily produces a lot of lather with soap.
• Solvent: It is a liquid.
• Stainless steel: It is iron containing 4 percent chromium to resist rusting.
• Steroids: Class of organic compounds present in animals and plants. These are present as bile acids.
• Sucrose: Cane Sugar made of glucose and fructose.
• Sulphur dioxide: It is a colourless gas which can make people cough.
• Surgical Spirit: It is ethanol to which has been added a small amount of methanol to render it unfit to drink.
• Synthetic: It describes an artificial substance.
• Thermodynamics: The branch of science dealing with the conversation of energy from one form to another,
especially heat and mechanical energy.
• Titanium: It is a chemical element, a hard, white metal which does not corrode easily.
• Toxin: A poisonous substance produced by a living organism, generally bacteria.
• Tungsten: It is a chemical element, a grey metal which has a very high melting point, Filaments in electric light
bulbs are made from tungsten.
• Urea: It is called carbamide, it is a white crystalline organic compound with m.p. 1330C, it is found in the urine.
• Unleaded petrol: Petrol manufactured without the addition of antiknock. It has a slightly lower octune rating than
leaded petrol, but has the advantage of not polluting the atmosphere with lead compounds.
• Vinegar: A solution which is made by the action of bacteria on wine or cider.
• Vitamins: Chemicals which are important to the proper working of the body. They tend to be complex organic
molecules which must be eaten, as in daily products are (Vitamin A) or fruit (Vitamin C).
• Vulcanization: A chemical process of improving the physical properties of natural rubber by heating it with sulphur.
