Model of the atom GapFill

All matter is made up of  ionsatomscellsenergy, which come in different types, called  atomselementsparticlesreactants, represented using symbols which can be found on the  periodic tablecompound sequencereactivity listInternet. When these react together,  mixturesbeta particlescompoundsatoms are formed, which have formulae to show the  importancepositionratiopercentage of each element.  MixturesNeutronsPure substancesElectrons contain multiple elements or compounds, and can be  separatedmeltedshapedreacted using filtration, distillation, crystallisation and chromatography.

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

• the  plum puddingdough ballupside-down pineappledoughnut model, where the atom is a ball of positive charge with electrons dotted around
• Rutherford's model - the  directionalnuclearconnectiveelectronic model - based on the observations of  metallicbeta particlealpha particlegamma particle scattering
•  Isaac NewtonMarie CurieNiels BohrNeil Armstrong's model, where electrons orbit the nucleus
•  James DaltonJames ChadwickDmitri MendeleevCharles Darwin's model, where neutrons are also in the nucleus

Different  subatomicmagneticalphainfrared particles have different masses and charges. Protons (positive particles) and neutrons (neutral particles) have a mass of  -111012, 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  bondsprotonsisotopessalts.