Whats the difference between atom, element, molecule and compound?
An element is a substance made up of one type of atom. An atom is the smallest divsible part of an element to maintain the properties of the element (atoms van be divided into smaller particles e.g. protons, electrons, but these do not display the properties of the element). A molecule is a group of atoms, not necessarily the same; for example a water molecule is comprised of 2 hyrdogen atoms and one oxygen atom. A compound is a complex substance made of several different types of moelcule.