They’re typically made up of three main parts: protons, neutrons and electrons. Think of the protons and neutrons as together forming a “sun”, or nucleus, at the centre of the system. The electrons orbit this nucleus, like planets. If atoms are impossibly small, these subatomic particles are even more so.

An element is a material that consists of a single type of atom. Each atom type contains the same number of protons. Chemical bonds link elements together to form more complex molecules called compounds. A compound consists of two or more types of elements held together by covalent or ionic bonds.

Only if the number of protons (and consequently the electrons) is different, the atoms are of two different elements. The number of neutrons in atoms of different elements can be the same and so can the number of neutrons in two atoms of the same element be different.

In order to clearly visualize atoms, a scanning tunneling microscope is used which is a microscope that uses electrons instead of light to see very small objects. The resolution of these microscopes is good enough so that individual atoms can be seen as bumps. All atoms will scatter some of the light that hits them.

All matter consists of indivisible particles called atoms. Atoms of the same element are similar in shape and mass, but differ from the atoms of other elements. Atoms cannot be created or destroyed. The atom is the smallest unit of matter that can take part in a chemical reaction.

Atoms cannot be created nor destroyed, and they are indestructible; they cannot be broken into smaller parts. This was based on the Law of Conservation of Mass. It was later learned that atoms can break into smaller parts. Chemical reactions involve a separation, combination, or rearrangement of atoms.