UK Chemistry Olympiad

Thermodynamic calculations and sherbet lemons | Chemistry Olympiad worked answers

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Try this worked example of a Chemistry Olympiad question, investigating properties of ingredients in sherbet lemons. Includes video walkthrough and transcript.

In this question from the 2006 UK Chemistry Olympiad round one paper, students apply their knowledge and understanding of a number of the ingredients in sherbet lemons to write a combustion equation for sugar, calculate energy released and investigate the structures of tartaric acid and citric acid. The accompanying video walkthrough is designed to help students if they get stuck or want to check their working.

The question is low difficulty, and covers the following chemistry topics:

  • Balancing combustion equations
  • Thermodynamic calculations
  • Mole calculations
  • The structures of tartaric acid and citric acid

Students first attempt to answer the question by themselves, before using the video walkthrough if they get stuck or want to check their working at the end.

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