two or more elements or compound not chemically joined
Pure substances
Pure substances are made from only one chemical element or one compound.
Impure substances
Impure substances are made from more than one element or one compound.
Seperation method: chromatography
A separation technique used to separate mixtures of soluble substances, usually coloured substances such as ink.
Seperation method: filtration
A seperation technique used to separate an insoluble solid from a pure liquid or a solution. The filtrate is the liquid which passes through the filter paper and the residue is the solid left on the filter paper.
Seperation method: Evapouration
A seperation technique used to sperate the solid solute from the solvent.
Seperation method: Distillation
A separation technique used to separate a solvent from a mixture. For example, water can be separated from salt solution by distillation. This involves boiling the mixture and then condensing the gas to produce a liquid.
