1bElements, compounds and mixtures

Syllabus objectives

• 1.8understand how to classify a substance as an element, compound or mixture
• 1.9understand that a pure substance has a fixed melting and boiling point, but that a mixture may melt or boil over a range of temperatures
• 1.10describe these experimental techniques for the separation of mixtures: • simple distillation • fractional distillation • filtration • crystallisation • paper chromatography.
• 1.11understand how a chromatogram provides information about the composition of a mixture
• 1.12understand how to use the calculation of Rf values to identify the components of a mixture
• 1.13practical: investigate paper chromatography using inks/food colouringsPractical