Question: what are molecules?

Matthew Pankhurst answered on 18 Jun 2013:

Hello mburdie312. A molecule is a group of atoms (2 or more) that are attached to each other. Some atoms naturally have what is called a “positive charge”, and some have “negative charge”. When a positive charged atom comes close to a negative charged atom, they attach a bit like magnets to each other (we call it ‘bonding’ – not like James Bond though!). From then on they get around together (or until something else breaks them up). For an example, hydrogen atoms each have one positive charge each, so we write it H+. Oxygen has two negative charges so we write it O2-. When two hydrogen atoms meet one oxygen atom they attach and become H2O – which is water! There are different types of bonding and lots of different elements, and some can have different charges too – so it’s a big chemical playground out there!