Atomic structure GapFill

All matter is made up of  chargesionsatomsenergy, which come in different types, called  moleculesatomsreactantselements, represented using symbols which can be found on the  reactivity listgroup seriesperiodic tableInternet. John Dalton developed his atomic theory, which stated that  atoms cannot be observedatoms can be created and destroyedall atoms are identicalatoms 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  electronsionsneutronsmolecules dotted around...
• Rutherford's model - the  electronicelasticconnectivenuclear model - based on the observations of  metallicbeta particlehalogenalpha particle scattering...
• Niels Bohr's model, where electrons orbit the  saltionnucleusisotope...
• and James Chadwick's model, where neutrons are also in the nucleus

Different  ultrasonicalphasubatomicomega particles have different masses and charges. Protons (positive particles) and neutrons (neutral particles) have a mass of  -11120.5, 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  compoundsprotonsisotopesions.