How do you find weight using volume?

Answer 1

If you know the volume of something you can find its weight (or mass) if you know it's density.

Density is a measure of a substances mass per unit volume.

So for example;

Q: How much does 0.5 litres of water weigh?

A: The density of water is roughly 1 gram per cm3. A cm3 is the same as a mL (millilitre), and there are 500 mL in a 0.5 litres.

So, weight = 1 g/mL * 500 mL = 500 g

You can find densities of various substances on the internet or in reference texts.