Experimental Techniques

2.1 Measurement
Core
• Name appropriate apparatus for the measurement of time, temperature, mass
and volume, including burettes, pipettes and measuring cylinders
2.2 Purity
2.2.1 Criteria of purity
Core
• Demonstrate knowledge and understanding of paper chromatography
• Interpret simple chromatograms
• Identify substances and assess their purity from melting point and boiling point information
• Understand the importance of purity in substances in everyday life, e.g. foodstuffs and
drugs
2.2.2 Methods of purification
Core
• Describe and explain methods of purification by the use of a suitable solvent, filtration,
crystallisation and distillation (including use of a fractionating column). (Refer to the fractional distillation of petroleum in section 14.2 and products of fermentation in section 14.6.)
• Suggest suitable purification techniques, given information about the substances involved
Supplement
• Interpret simple chromatograms, including the use of Rf values
• Outline how chromatography techniques can be applied to colourless substances by exposing chromatograms to substances called locating agents. (Knowledge of specific locating agents is not required.)Chap#2 Experimental Techniques