Model of the atom GapFill

All matter is made up of  cellsionsenergychargesmoleculesatoms, which come in different types, called  metalsatomsparticleselementsreactantsmolecules, represented using symbols which can be found on the  periodic tableatomic modelInternetcompound sequencereactivity listgroup series. When these react together,  atomsnoble gasesprotonsbeta particlescompoundsmixtures are formed, which have formulae to show the  chargepercentagepositionimportancesizeratio of each element.  MixturesElectronsPure substancesHalogensMetalsNeutrons contain multiple elements or compounds, and can be  shapedfusedmeltedreactedseparatedbonded using filtration, distillation, crystallisation and chromatography.

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

• the  doughnutcheesecakedough ballplum puddingupside-down pineapplestrawberry shortcake model, where the atom is a ball of positive charge with electrons dotted around
• Rutherford's model - the  connectiveelasticdirectionalmagneticelectronicnuclear model - based on the observations of  radiationhalogenalpha particlemetallicbeta particlegamma particle scattering
•  Isaac NewtonNeil ArmstrongNiels BohrAlbert EinsteinMarie CurieTheodore Roosevelt's model, where electrons orbit the nucleus
•  Dmitri MendeleevJames ChadwickCharles DarwinAlexander FlemingJames DaltonFrancis Drake's model, where neutrons are also in the nucleus

Different  alphaultrasonicmagneticinfraredomegasubatomic particles have different masses and charges. Protons (positive particles) and neutrons (neutral particles) have a mass of  -1101220.51, 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  ionsisotopesbondssaltscompoundsprotons.