Model of the atom GapFill

All matter is made up of  energychargescellsmoleculesionsatoms, which come in different types, called  atomsmetalsreactantsparticlesmoleculeselements, represented using symbols which can be found on the  compound sequenceperiodic tableatomic modelInternetreactivity listgroup series. When these react together,  mixturesbeta particlesprotonsatomscompoundsnoble gases are formed, which have formulae to show the  ratiopositionchargepercentageimportancesize of each element.  HalogensNeutronsElectronsPure substancesMetalsMixtures contain multiple elements or compounds, and can be  fusedbondedseparatedshapedreactedmelted using filtration, distillation, crystallisation and chromatography.

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

• the  cheesecakeupside-down pineappledoughnutplum puddingdough ballstrawberry shortcake model, where the atom is a ball of positive charge with electrons dotted around
• Rutherford's model - the  nuclearmagneticdirectionalconnectiveelectronicelastic model - based on the observations of  metallicradiationbeta particlegamma particlehalogenalpha particle scattering
•  Albert EinsteinMarie CurieNiels BohrNeil ArmstrongIsaac NewtonTheodore Roosevelt's model, where electrons orbit the nucleus
•  Francis DrakeJames ChadwickJames DaltonDmitri MendeleevCharles DarwinAlexander Fleming's model, where neutrons are also in the nucleus

Different  infraredsubatomicomegamagneticultrasonicalpha particles have different masses and charges. Protons (positive particles) and neutrons (neutral particles) have a mass of  1021-10.512, 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  isotopesprotonsbondssaltscompoundsions.