Properties of Matter

Paperclip Afloat

Enrichment Activity for 5-11 11-14


What you need

  • A paperclip
  • A cereal bowl
  • Water
  • Washing-up liquid
  • A tissue

Instructions

  1. Put the paperclip on a flat piece of tissue in the empty bowl.
  2. Fill the bowl with water, being careful not to pour water directly on top of the paperclip and tissue.
  3. The tissue will sink as it absorbs water, but the paperclip will float! Now put a drop of washing-up liquid in the bowl. The paperclip will sink!

Results and Explanation

Though the paperclip should be heavy enough to sink, the surface tension of the water holds it up. When the washing-up liquid dissolves in the water it lowers the overall surface tension, so the paperclip sinks.

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