1. What is matter?

Abstract

Matter is the stuff from which everything in the world is made. ‘What is matter?’ explains that all things are made of atoms. Inside every atom is a tiny nucleus, and, surrounding the nucleus, a cloud of electrons. The nucleus is made out of protons and neutrons, and, inside, there are smaller particles, quarks. As far as we know, electrons and quarks are not made from anything smaller and so they are fundamental particles. Matter exists in forms of immense variety and complexity; there are ninety-two naturally occurring chemical elements, which can form billions of different molecules. The scale of matter is also described.