Atomic structure GapFill

All matter is made up of  ionsatomsenergycharges, which come in different types, called  reactantselementsatomsmolecules, represented using symbols which can be found on the  periodic tablereactivity listInternetgroup series. John Dalton developed his atomic theory, which stated that  atoms cannot be observedatoms cannot be broken into smaller partsatoms can be created and destroyedall atoms are identical.

Over time, different scientists have developed new models of the atom. These include:

• the plum pudding model, where the atom is a ball of positive charge with  ionselectronsneutronsmolecules dotted around...
• Rutherford's model - the  nuclearelectronicelasticconnective model - based on the observations of  alpha particlebeta particlehalogenmetallic scattering...
• Niels Bohr's model, where electrons orbit the  saltionnucleusisotope...
• and James Chadwick's model, where neutrons are also in the nucleus

Different  subatomicultrasonicomegaalpha particles have different masses and charges. Protons (positive particles) and neutrons (neutral particles) have a mass of  -11210.5, and electrons (negative particles) have a very small mass. The relative atomic mass of an atom is the weighted average mass of all of the element's  ionscompoundsisotopesprotons.