Which statement about the physical properties of a substance containing impurities is correct?
Impurities decrease the melting point and increase the boiling point of the substance.
Impurities increase the melting point and decrease the boiling point of the substance.
Impurities cause the substance to melt at a sharp, single temperature.
Impurities do not change the temperature range over which the substance melts.
46 exam-style questions on OCR GCSE Chemistry Purity and separating mixtures. Each one has a worked solution and a mark scheme showing where the marks go.