Atomic structure GapFill

All matter is made up of  energycellschargesionsatomsmolecules, which come in different types, called  elementsmetalsatomsreactantsmoleculesparticles, represented using symbols which can be found on the  Internetreactivity listgroup seriescompound sequenceatomic modelperiodic table. John Dalton developed his atomic theory, which stated that  atoms are small, cube-shaped particlesatoms in an element are all uniqueall atoms are identicalatoms cannot be observedatoms can be created and destroyedatoms cannot be broken into smaller parts.

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  neutronsisotopesprotonsionselectronsmolecules dotted around...
• Rutherford's model - the  nuclearelasticelectronicdirectionalmagneticconnective model - based on the observations of  alpha particleradiationgamma particlehalogenmetallicbeta particle scattering...
• Niels Bohr's model, where electrons orbit the  ionisotopemetalnucleussaltsubatomic particle...
• and James Chadwick's model, where neutrons are also in the nucleus

Different  ultrasonicalphamagneticomegainfraredsubatomic particles have different masses and charges. Protons (positive particles) and neutrons (neutral particles) have a mass of  0.5122-1110, 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  ionssaltsbondscompoundsprotonsisotopes.