Experimental Chemistry structured questions · SEC G3 Pure Chemistry

Learning objectives

• name appropriate apparatus for the measurement of time, temperature, mass and volume; including burettes, pipettes, measuring cylinders and gas syringes
• suggest suitable apparatus, given relevant information, for a variety of simple experiments, including drying and collection of gases and measurement of rates of reaction (drying agents will be limited to calcium oxide, concentrated sulfuric acid and fused calcium chloride).
• describe methods of separation and purification for the components of mixtures, to include: — use of a suitable solvent, filtration and crystallisation or evaporation
• describe methods of separation and purification for the components of mixtures, to include: — sublimation
• describe methods of separation and purification for the components of mixtures, to include: — distillation and fractional distillation (see also 11.1(b))
• describe methods of separation and purification for the components of mixtures, to include: — use of a separating funnel
• describe methods of separation and purification for the components of mixtures, to include: — paper chromatography
• suggest suitable separation and purification methods, given information about the substances involved in the following types of mixtures: — solid-solid
• suggest suitable separation and purification methods, given information about the substances involved in the following types of mixtures: — solid-liquid
• suggest suitable separation and purification methods, given information about the substances involved in the following types of mixtures: — liquid-liquid (miscible and immiscible)
• interpret paper chromatograms including comparison with ‘known’ samples and the use of Rf values
• explain the need to use locating agents in the chromatography of colourless compounds (knowledge of specific locating agents is not required)
• deduce from given melting point and boiling point data the identities of substances and their purity.
• explain the importance of measuring the purity in substances used in everyday life, e.g. foodstuffs and drugs.
• follow a sequence of instructions;
• use techniques, apparatus and materials;
• make and record observations, measurements and estimates;
• interpret and evaluate observations and experimental results;
• plan investigations, select techniques, apparatus and materials;
• evaluate methods and suggest possible improvements.