Eli5: How does water expand in a closed container? Shouldn’t it shrink and be compact as it forms into a solid which has tighter molecules?

Question

Context: I was trying to figure out why my coke glass bottle exploded in my freezer.

Update: As it turns out, water is a weird one amongst other liquids.

In: 3

Answer 1

Water does, in fact, shrink as it cools. However, as it freezes the hydrogen atoms of each molecule want to bond with each other and that forces the molecules to push apart to form those bonds.

Think about it like this: you get a bunch of people and squeeze them closer and closer together. This is the water cooling. Now, in order to form a solid, everyone needs to hold hands. You can imagine that since the people are so close together they need to push apart a little to be able to actually hold hands. This is like the water starting to freeze. As more bonds are made (hand holding) they need to spread further out because their bodies are in the way.

Edit: as u/Saavedroo pointed out below, my analogy here implies the hydrogen bonds with each other instead of with the oxygen. I made a slight edit for more clarity but in hindsight I should have replaced “hold hands” with “place a hand on another’s shoulder.”