Water has many interesting characteristics. Did you know that water molecules are sticky? They stick to each other and everything else that is water-soluble because of surface tension. This attribute allows you to create a dome of water on top of a coin. Try for yourself!

Equipment

  • An eyedropper
  • Water
  • A coin

Instructions

  1. Fill the eyedropper with water. If you’re using a straw, suck water into the straw and then keep it in place by sealing the top shut with a finger. Release water little by little by removing your finger.
  2. Dispense water onto the coin, one drop at a time. How many can you fit? Try looking at the coin from the side once you have created a dome.

What happens?

Water molecules want to stick to each other because of surface tension. Surface tension allows you to create a dome on top of the coin before it overflows. Try changing the variables after you’ve done the experiment once. Does it make a difference if the coin is clean or dirty? What happens if you place a drop of dish soap on top of the coin?

 

 

Water has many interesting characteristics. Did you know that water molecules are sticky? They stick to each other and everything else that is water-soluble because of surface tension. This attribute allows you to create a dome of water on top of a coin. Try for yourself! Equipment An eyedropper Water A coin Instructions Fill the….Click to read more