Methods of Purification & Analysis Notes

Methods of Purification and Analysis

Learning Outcomes

(a) describe methods of separation and purification for the components of mixtures, to include: (i) use of a suitable solvent, filtration and crystallisation or evaporation (ii) sublimation (iii) distillation and fractional distillation (iv) use of a separating funnel (v) paper chromatography. 

(b) suggest suitable separation and purification methods, given information about the substances involved in the following types of mixtures: (i) solid-solid (ii) solid-liquid (iii) liquid-liquid (miscible and immiscible). 

(c) interpret paper chromatograms including comparison with ‘known’ samples and the use of Rf values. 

(d) explain the need to use locating agents in the chromatography of colourless compounds (knowledge of specific locating agents is not required). 

(e) deduce from given melting point and boiling point data the identities of substances and their purity. 

(f) explain the importance of measuring the purity in substances used in everyday life, e.g. foodstuffs and drugs.