# ELi5 How come increasing volume doesn’t affect mass?

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How come increasing volume doesn’t affect mass?
So I understand mass isn’t weight, mass is the amount of matter in an object

In: Chemistry

~~Can you give me an example when it doesn’t affect mass? Unless the mass is 0, increasing the volume will increase its mass. Are you talking about density?~~

Edit: Well, I need to take a sleep

If you increase the volume of something, you’re increasing the amount of material you have.

So if the density stays the same, you are absolutely increasing its mass.

Volume is just the amount of space that something takes up. On its own, it has nothing to do with mass. Increasing volume without increasing mass means that the same amount of matter is spread out over more space—in other words, the *density* decreases.

You can increase volume without changing mass by adding more empty space between the particles.

Let’s look at the way ice forms.

When you freeze water in an ice tray, the frozen ice will be bigger and take up more space than the liquid water does. So the *volume* increases while the *amount* of water stays the same (ie mass).

How? Because when water freezes, the water molecules organize themselves into a crystallized shape, and the crystal formation has more space between the molecules than liquid water.