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Brainlag Learn / GCSE Chemistry

Chemical analysis

Purity and formulations, chromatography and Rf values, tests for gases, and for separate Chemistry the tests for ions and flame emission spectroscopy.

Lessons

  1. Pure substances and formulationsWhat pure means to a chemist, how melting and boiling points reveal impurities, and the percentages in a formulation. 20 min, free
  2. Required practical: chromatographyRunning a paper chromatogram, the two phases, Rf values measured from the start line, repeats and identifying substances. 25 min, free
  3. Tests for gasesThe tests and positive results for hydrogen, oxygen, carbon dioxide and chlorine, and which reactions give which gas. 15 min, Plus
  4. Required practical: identifying ionsFlame tests, metal hydroxide precipitates, and the tests for carbonate, halide and sulfate ions, put together to name an unknown salt. 25 min, Plus, Chemistry only
  5. Instrumental methodsFlame emission spectroscopy, reading line spectra to find the metal ions in a mixture, and concentrations from a calibration line. 20 min, Plus, Chemistry only

Practise and test

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