Model of the atom GapFill

All matter is made up of  moleculescellsionsatomschargesenergy, which come in different types, called  elementsmetalsatomsreactantsparticlesmolecules, represented using symbols which can be found on the  reactivity listatomic modelInternetcompound sequencegroup seriesperiodic table. When these react together,  beta particlescompoundsatomsnoble gasesmixturesprotons are formed, which have formulae to show the  positionchargesizeratiopercentageimportance of each element.  NeutronsPure substancesMetalsMixturesHalogensElectrons contain multiple elements or compounds, and can be  meltedbondedseparatedshapedfusedreacted using filtration, distillation, crystallisation and chromatography.

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

• the  plum puddingupside-down pineapplecheesecakedough ballstrawberry shortcakedoughnut model, where the atom is a ball of positive charge with electrons dotted around
• Rutherford's model - the  connectivenucleardirectionalelectronicelasticmagnetic model - based on the observations of  metallichalogengamma particlealpha particlebeta particleradiation scattering
•  Isaac NewtonNiels BohrAlbert EinsteinMarie CurieTheodore RooseveltNeil Armstrong's model, where electrons orbit the nucleus
•  Alexander FlemingJames DaltonJames ChadwickFrancis DrakeCharles DarwinDmitri Mendeleev's model, where neutrons are also in the nucleus

Different  alphainfraredomegaultrasonicsubatomicmagnetic particles have different masses and charges. Protons (positive particles) and neutrons (neutral particles) have a mass of  1120.5102-1, 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  bondsprotonsisotopescompoundsionssalts.