Properties of Matter

Diffusion of copper sulfate crystals in water

Practical Activity for 14-16 PRACTICAL PHYISCS


Apparatus and Materials

  • Gas jar
  • Cover glass
  • Copper sulfate crystals (harmful)

Health & Safety and Technical Notes

Warn students who might try to taste copper sulfate that it is harmful if swallowed.

Read our standard health & safety guidance

Put a layer of large copper sulfate crystals in a gas jar of water with a cover glass over the top.


  1. Show the newly-filled gas jar.
  2. Leave undisturbed for several weeks.
  3. Get the class to check the gas jar each week.

Teaching Notes

After several weeks, the blue of the copper sulfate will diffuse into the water. Obviously, it is helpful if the jar is not moved or knocked.

This experiment was safety-tested in February 2006

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