noun

a substance in which bacteria and other microorganisms are grown in laboratories

noun

a chemical that you add to the water in a car engine to prevent it from freezing

noun

a substance that prevents oxygen from combining with other substances and damaging them. Antioxidants are used in industry for making substances such as rubber and plastic stronger, and they are often added to processed foods to make them stay fresh for longer.

noun

a substance used for giving something a different colour or for making its colour stronger

noun

a substance that you add to change the colour of something

noun

a chemical used for making the leaves fall off a tree or plant

noun

a chemical substance used to break up a liquid, especially oil floating on the sea, into tiny pieces so that it spreads over a wide area and causes less harm

noun

solid carbon dioxide that is used for keeping things cold and for producing white smoke in plays and at concerts

noun

a substance used for causing explosions, especially for breaking rock into pieces

noun

a clear liquid that is used as a solvent (=a mixture that changes solid substances into liquids) or for making people unconscious

noun

a chemical made by mixing formaldehyde with water, used for preserving dead things in a laboratory

noun

a substance used to cause explosions, especially under water

noun

a substance that is used for causing explosions or for making fireworks (=objects that burn to produce noise and coloured light)

noun

a substance that produces a quick and powerful explosion and is often used in bombs

noun

a chemical compound that changes colour in particular conditions. It can be used to test chemical substances, for example in order to discover how acid or alkaline something is.

noun

a clear liquid consisting of calcium hydroxide and water. It is used to test for carbon dioxide as it stops being clear when carbon dioxide is put through it.

noun

a substance that is used in chemical tests to discover whether a substance is an acid or an alkali

noun

a chemical substance containing nitrogen, used for improving the quality of soil

noun

a chemical used for making bombs and some types of medicine

noun

a chemical in petrol, used for measuring its quality

noun

a chemical made from coal, used for killing bacteria

noun

a chemical that contains phosphorus, used especially for making plants grow

noun

a soft substance that can explode, or a bomb made from this substance

noun

a substance used in a chemical reaction

noun

a substance that is used in making matches and fireworks

a plastic substance that can be bent into any shape and is used for making bombs

noun

a chemical with a very strong smell, held under the nose of an unconscious person to make them conscious again

noun

a liquid used for dissolving a solid substance so that it becomes part of the liquid

noun

a chemical solution that changes to different colours depending on how acid or alkaline the substance being tested is