UK Chemistry Olympiad

Titration and phosphates in the environment | Chemistry Olympiad worked answers

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Have a go at a worked example of a Chemistry Olympiad question on the use of titration to determine phosphate levels. Includes video walkthrough and transcript.

In this question from the 2007 UK Chemistry Olympiad round one paper, students read about the effects of excess phosphate levels in our water supply and in the blood. They then learn how ammonium molybdate can be used to set up a titration to measure the concentration of phosphate ions in solution, before the question probes this topic in greater depth. The accompanying video walkthrough is designed to help students if they get stuck or want to check their working.

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

  • Neutralisation reactions
  • Titration calculations
  • pH calculations
  • Balancing equations

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