Model of the atom GapFill

All matter is made up of  cellsenergychargesionsmoleculesatoms, which come in different types, called  reactantsmoleculeselementsatomsparticlesmetals, represented using symbols which can be found on the  group seriesInternetcompound sequencereactivity listatomic modelperiodic table. When these react together,  beta particlesatomscompoundsmixturesprotonsnoble gases are formed, which have formulae to show the  importancesizepercentagechargepositionratio of each element.  MetalsNeutronsElectronsPure substancesHalogensMixtures contain multiple elements or compounds, and can be  meltedshapedfusedbondedreactedseparated using filtration, distillation, crystallisation and chromatography.

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

• the  upside-down pineappleplum puddingstrawberry shortcakedough balldoughnutcheesecake model, where the atom is a ball of positive charge with electrons dotted around
• Rutherford's model - the  magneticnuclearconnectivedirectionalelasticelectronic model - based on the observations of  alpha particlegamma particleradiationmetallichalogenbeta particle scattering
•  Theodore RooseveltNiels BohrIsaac NewtonAlbert EinsteinMarie CurieNeil Armstrong's model, where electrons orbit the nucleus
•  Francis DrakeJames ChadwickCharles DarwinAlexander FlemingJames DaltonDmitri Mendeleev's model, where neutrons are also in the nucleus

Different  omegainfraredalphamagneticultrasonicsubatomic particles have different masses and charges. Protons (positive particles) and neutrons (neutral particles) have a mass of  12-111020.5, 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  compoundsbondsionsisotopesprotonssalts.