Question: what is a molecule

Katherine Manfred answered on 25 Nov 2020:

As Juan mentioned, molecules are made of atoms. Atoms are the basic unit of each element (like on the periodic table which you might have in a classroom) – they are like different coloured Lego blocks, and we put them together in different arrangements to make molecules. Some molecules are really, really small – only two atoms (like the oxygen gas you breathe in to stay alive!); others are made up of thousands of atoms (like the proteins in your body that also keep you alive!). When the molecules break apart or combine together – like playing with Lego bricks – we call that a chemical reaction because the molecule we started with is different from the molecule we end up with.