Properties of Matter

Bubble Race

Enrichment Activity for 5-11 11-14

What you need

  • Two glasses
  • Skimmed milk
  • Whole milk
  • Two straws
  • A friend


  1. Pour about five centimetres of skimmed milk in to one glass and the same amount of whole milk in to the other glass
  2. Both starting at the same time, blow through the straws and into the milk

Results and Explanation

The skimmed milk froths up much faster than the whole milk, and the bubbles last longer too!
Bubbles can form in milk because the milk proteins form a strong skin. But the fat in whole milk interacts with these proteins, weakening this skin and popping the bubbles.

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