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The experiment will allow students to construct a simple hydrometer using a drinking straw and blu tack and also allow them to investigate the density of household liquids. This experiment can also be expanded to provide a problem solving experiment that the students can undertake themselves.

Suggested teaching points

  • Density
  • Physical propertise of substances
  • Analytical skills
  • Problem solving skills and data interpretation

This file contains a set of detailed instructions, suggested questions, suggested improvements and disposal procedures for this experiment.

(PDF Document) Hydrometer experiment instructions

Before attempting this experiment, please ensure that you have read the safety section in the document above and performed a complete risk assessment. If you have any questions, comments or feedback, please use these forms.