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Science Project: Float An Egg Viewed: 5197
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Make An Egg Float

No, this is not a riddle. You will also find out why it is easier to swim in salt water than fresh.

What You Need:

  • An Egg
  • 12 tablespoons or more of salt
  • A glass of water

What To Do:

  • Put an egg in a glass half full of water. Notice what happens. Add several tablespoons of salt, stir gently, and observer what happens.
  • Remove the egg.
  • Now to the half  glass of salty water (10 tablespoons or more of salt), slowly fill the glass with fresh water. Don't stir.  Gently lower the egg into the glass.

What Happened:

  • In the fresh water the egg sank. As you added salt it started to float.
  • When you added fresh water to the very salty water, the egg started to float in the middle.

Why:

  • The denser the liquid the greater its upward lift (buoyancy). Salt make the water denser.
  • When you add fresh water to the salty water, it remains on top. The egg sinks through it and floats on the lower, denser, salt water.