Glossary
- atomThe smallest part of an element that can exist.
- boiling pointThe temperature at which a substance rapidly changes from a liquid to a gas.
- chromatogramThe results of separating mixtures by chromatography.
- chromatographyChromatography is used to separate different substances dissolved in a liquid.
- compoundA substance formed by the chemical union of two or more elements.
- concentrationThe concentration of a solution tells us how much of a substance is dissolved in water. The higher the concentration, the more particles of the substance are present.
- condensedTurned from a gas or vapour into a liquid, usually as a result of cooling.
- crude oilMixture of hydrocarbons, mainly alkanes, formed over millions of years from the remains of ancient dead marine organisms.
- crystalA solid containing particles (atoms, molecules or ions) joined together to form a regular arrangement or repeating pattern.
- crystallisationThe process of producing crystals from a solution by evaporating the solvent.
- dissolvedA substance is said to be dissolved when it breaks up and mixes completely with a solvent to produce a solution.
- elementA substance made of one type of atom only.
- ethanolThe alcohol which is produced as a result of fermentation of sugars by yeast.
- evaporationThe process in which a liquid changes state and turns into a gas.
- excessIn chemistry, a substance is in excess if there is more than enough of it to react with another reactant.
- filtrationMethod used to separate an insoluble solid from a liquid using a physical barrier such as paper.
- fractionIn fractional distillation, such as that of crude oil, the different parts of the original mixture are called fractions. The substances in each fraction have similar boiling points to each other.
- fractional distillationIn fractional distillation a mixture of several substances, such as crude oil, is distilled and the evaporated components are collected as they condense at different temperatures.
- freezeA change of state in which liquid becomes solid by cooling.
- groundwaterWhere water is stored in rocks beneath the ground.
- insolubleUnable to dissolve in a particular solvent. For example, sand is insoluble in water.
- ionElectrically charged particle, formed when an atom or molecule gains or loses electrons.
- meltingThe process that occurs when a solid turns into a liquid when it is heated.
- melting pointThe temperature at which a solid changes into a liquid as it is heated.
- micro organismsMicroscopic living things such as archaea, bacteria and some species of eukaryotes.
- mixtureTwo or more substances that are not joined together. The substances can be elements, compounds, or both.
- mobile phasePhase in chromatography that moves, usually a solvent or mixture of solvents.
- moleculeA collection of two or more atoms held together by chemical bonds.
- particleA general term for a small piece of matter. For example, protons, neutrons, electrons, atoms, ions or molecules.
- potableWater that is safe to drink.
- pureA substance that consists of only one element or only one compound.
- reactantA substance that reacts together with another substance to form products during a chemical reaction.
- simple distillationSeparation method used to separate a solvent from a solution.
- solubleAble to dissolve in solvent. For example, sugar is soluble in water because it dissolves to form sugar solution.
- soluteThe dissolved substance in a solution.
- solutionMixture formed by a solute and a solvent.
- solventThe liquid in which the solute dissolves to form a solution.
- stationary phasePhase in chromatography that does not move, for instance, the paper in chromatography.
- vapourGas formed below the boiling point of a substance.
