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Why do ice cubes float? |
Everything Water
Ice is frozen water, which is one of the most common substances on our planet! We see ice cubes floating in our drinks. It doesn’t seem strange at all, but actually, water is really weird! In nature, when almost all other liquids freeze, they would sink in their own liquid form. But not water! It floats right to the top.
It happens because when water freezes, it gets really well organized! All of the very tiny, microscopic pieces that make it up spread out evenly! They act sort of like magnets and push and pull away from each other, causing them to line up in the shapes of hexagons. When water is a liquid, it doesn’t have these shapes and the pieces that make it up can flow right past each other. They can squish together and fit more of themselves in a smaller space! As a solid (ice), the pieces of water are more spread out! They take up more space.
A piece of liquid water and a piece of solid water the same size would have very different weights! The solid water would be lighter, that’s why it floats on the heavier liquid water. In fact, most liquids are heavier than ice!
It’s a good thing ice floats because during wintertime, when lakes freeze, only the top parts freeze. All the fish and other animals living at the bottom of the lakes are still in liquid water, so they can survive the whole winter!
Liquid Layers!
Do you think ice would float on oil? Oil floats on water, so would ice float on it too? Or would it sink? Try this experiment at home with grown-up supervision.
Find a tall thin glass or small vase and fill it half way with water. On top of the water, add an inch or two of cooking oil. You’ll see that the oil and water don’t mix! You can even stir them up; after a while, they will separate. The oil will float! Now, add an ice cube? What happens? Why do you think the ice floats where it does?
What do you think will happen when the ice cube starts to melt? You just might see a little bit of water raining through the oil!
