Chemical Analysis

1 Pure Substances Define a pure substance in chemistry and use melting/boiling point data to assess purity. Spec 5.8.1.1 2 Formulations Define a formulation and give examples of common formulations. Spec 5.8.1.2 3 Chromatography Describe paper chromatography, calculate Rf values and use chromatography to identify substances. Spec 5.8.1.3 4 Testing for Gases Describe the tests for hydrogen, oxygen, carbon dioxide and chlorine. Spec 5.8.2.1–5.8.2.4 5 Flame Tests Identify metal ions using flame tests and describe the colours produced by each metal. Spec 4.8.3.1 6 Metal Hydroxides Identify metal ions by the colour of precipitate formed with sodium hydroxide solution. Spec 4.8.3.2 7 Tests for Carbonates, Halides and Sulfates Identify carbonate, halide and sulfate ions using chemical tests. Spec 4.8.3.3–4.8.3.5 8 Instrumental Methods and Flame Emission Spectroscopy Describe the advantages of instrumental analysis and explain how flame emission spectroscopy identifies metal ions. Spec 4.8.3.6–4.8.3.7