What is a pure substance in chemistry? Learn about pure and impure substances in this KS3 chemistry guide from BBC Bitesize.

Although children’s chemistry kits were first manufactured in the 18th century, it wasn’t until around the time of the Great Depression that they became a popular toy.The marketing was simple ...

Mixtures - AQA Pure substances and mixtures There are different ways to separate mixtures, such as filtration, crystallisation, simple distillation, fractional distillation and chromatography.