There are lots of different substances but only just over a hundred elements. An element is a substance that is made up of only one kind of atom. The atoms in a particular element are the same as each ...

Liquids and solutions may seem simple, but at the molecular level they are constantly in motion. When sugar dissolves in water, for example, each ...

There are different ways to separate mixtures, for example by filtration, crystallisation, distillation, or chromatography. The method chosen depends upon the type of mixture. Periodic table - OCR ...