What is the difference between mass and substance?

1 Answer
Sep 29, 2014

In chemistry, mass is a measure of the amount of matter in an object. For example, a person may have a mass of 55 kg.

A substance is a material with a constant chemical composition and characteristic properties. Water is a chemical substance.

You might say, for example, that 250 mL of water has a mass of 250 g.