Why do drinks in the freezer expand?


I looked it up but I still don’t understand, if the cells in liquid are jiggling around, shouldn’t they need to condense to become a solid? Like how if you have a bunch of packing peanuts, if you shake the box, they’ll move around a lot, whereas, if you squish them down into a block, they’ll condense, and not move. Sorry that’s the best analogy I could think of I just don’t get it.

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Water is interesting in that it does contract as it cools, but only to a certain temperature. When it freezes, it rearranges into a crystal pattern, which means it takes up a bit more space. Imagine a piece of flatpack furniture assembled into a bookshelf or what have you. Water’s freezing is just that happening. That’s also why ice floats on liquid water– it’s less dense thanks to its crystalline structure.

Your analogy is mostly correct and it’s the case for most liquids: usually when you freeze a liquid it shrinks.

But water is different. It’s because of the particular shape of water molecules. It kind of looks like a Mikey mouse face with the big oxygen and the two smaller hydrogens. In liquid form, they run around freely and can intertwine like peanut shaped packing peanuts. But when freezing, the oxygen and hydrogen atoms act like magnets and this creates forces that are stronger than the usual “much them all together” ones that bond other solids. With the particular shape of the molecule this makes a structure that is actually less packed than you could get by just muching everything together, so it takes up more space, causing the drink in general to expand.

In a liquid, the molecules are being shaken around enough that they can’t line up with eachother. When crystalline solids (like ice) form, they settle down and line up. Sort of like magnets snapping together.

Usually, even when they’re lined up, they’re smaller than the liquid state, but in the case of water they actually spread out a bit.

The reasons why water expands when it freezes, unlike most liquids which contract, is poorly understood, even by chemists and physicists. It’s an area of ongoing research.