Why does ice float in water? - George Zaidan and Charles Morton?

Ice floats in water because it is lighter than the same amount of liquid water.

Imagine you have a cup full of water, and you freeze it. When it turns into ice, it doesn’t get bigger, it actually gets less dense. That means if you take the same space that was filled with water and turn it into ice, it weighs less. Because it’s lighter, it can float on top of the water like a little boat.

When water freezes, its molecules move apart and form a special shape, kind of like how your toys spread out when you take them out of a box. In liquid water, the molecules are moving around more freely, but in ice, they lock into place in a pattern that takes up more space. Even though it looks like ice is taking up more room than water, it’s actually lighter for the same size.

So next time you see an ice cube floating in your drink, remember, it's just doing what all light things do: float!