The “lead” of a pencil is actually made of a substance called graphite which is made of carbon atoms. The picture shows a close-up of one carbon atom. A hydrogen atom has one proton as the nucleus and ...

When two hydrogen atoms get close enough, the electron from each atom feels an attraction from the proton in the other atom's nucleus. This attraction pulls the atoms together. The electrons end up ...

The number of electron shells of all the elements in a period is the same as the period number. Similarly, the atoms of all group 7 elements have similar chemical properties and reactions to each ...

The electronic structure of atoms and molecules is the series of energy levels that it are possible for a bound electron to occupy. This electronic structure determines many of the defining ...

Electrons move in fixed orbits, called electron shells, around the nucleus. New evidence The discovery of electrons. Changes to the atomic model Atoms can be broken down into smaller parts.