Key fact An impure substance is a type of mixture, so melting points can be used to find out if a substance is pure or impure. Impure substances tend to have a slightly lower melting point than ...

Either evaporation or crystallisation can be used to separate a solid solute from a solution. Learn more in this KS3 Chemistry guide from Bitesize. Distillation Distillation is a separation ...

The North Korean authorities have ordered crackdowns on the distribution of "impure" South Korean media and foreign ...

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