Atomic structure GapFill

All matter is made up of  atomsmoleculesenergychargesionscells, which come in different types, called  metalsatomselementsmoleculesreactantsparticles, represented using symbols which can be found on the  reactivity listperiodic tableatomic modelcompound sequencegroup seriesInternet. John Dalton developed his atomic theory, which stated that  atoms cannot be broken into smaller partsall atoms are identicalatoms are small, cube-shaped particlesatoms can be created and destroyedatoms cannot be observedatoms in an element are all unique.

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  isotopesmoleculesneutronsionsprotonselectrons dotted around...
• Rutherford's model - the  directionalnuclearmagneticconnectiveelectronicelastic model - based on the observations of  radiationbeta particlehalogenmetallicalpha particlegamma particle scattering...
• Niels Bohr's model, where electrons orbit the  metalsaltsubatomic particleionnucleusisotope...
• and James Chadwick's model, where neutrons are also in the nucleus

Different  ultrasonicalphamagneticsubatomicinfraredomega particles have different masses and charges. Protons (positive particles) and neutrons (neutral particles) have a mass of  12-120.5110, 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  protonsisotopesbondscompoundsionssalts.