Fill the jar about halfway with warm water. Then, add salt until it no longer dissolves when mixed.
Carefully put in the egg. Your egg should float to the top of the water!
Hold a spoon upside down over the jar and pour warm water over it. Fill up the jar the rest of the way. The egg stays in the same place!
The salt water is saturated with the salt, which makes it more dense. The egg is less dense than the salt water, so the it floats to the top. When the fresh water is poured into the jar, it also floats above the salt water. However, the water on its own is less dense than the egg, so the egg doesn’t move. The egg floats at the top of the salt water, but sinks below the fresh water! Cool!
Experiment further with a hard boiled egg!
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