Model of the atom GapFill

All matter is made up of  cellsenergyatomsions, which come in different types, called  atomsreactantsparticleselements, represented using symbols which can be found on the  Internetreactivity listperiodic tablecompound sequence. When these react together,  atomsbeta particlesmixturescompounds are formed, which have formulae to show the  importanceratiopercentageposition of each element.  ElectronsNeutronsMixturesPure substances contain multiple elements or compounds, and can be  reactedmeltedseparatedshaped using filtration, distillation, crystallisation and chromatography.

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

• the  upside-down pineappledoughnutplum puddingdough ball model, where the atom is a ball of positive charge with electrons dotted around
• Rutherford's model - the  connectivedirectionalelectronicnuclear model - based on the observations of  metallicgamma particlebeta particlealpha particle scattering
•  Niels BohrIsaac NewtonNeil ArmstrongMarie Curie's model, where electrons orbit the nucleus
•  James DaltonCharles DarwinJames ChadwickDmitri Mendeleev's model, where neutrons are also in the nucleus

Different  alphasubatomicmagneticinfrared particles have different masses and charges. Protons (positive particles) and neutrons (neutral particles) have a mass of  12-1110, 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  isotopesprotonssaltsbonds.