Model of the atom GapFill

All matter is made up of  atomscellsenergyions, which come in different types, called  particlesatomselementsreactants, represented using symbols which can be found on the  Internetreactivity listcompound sequenceperiodic table. When these react together,  compoundsmixturesatomsbeta particles are formed, which have formulae to show the  percentageratioimportanceposition of each element.  MixturesNeutronsElectronsPure 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  dough balldoughnutupside-down pineappleplum pudding model, where the atom is a ball of positive charge with electrons dotted around
• Rutherford's model - the  connectiveelectronicdirectionalnuclear model - based on the observations of  gamma particlemetallicbeta particlealpha particle scattering
•  Niels BohrNeil ArmstrongIsaac NewtonMarie Curie's model, where electrons orbit the nucleus
•  James ChadwickDmitri MendeleevCharles DarwinJames Dalton's model, where neutrons are also in the nucleus

Different  alphainfraredsubatomicmagnetic particles have different masses and charges. Protons (positive particles) and neutrons (neutral particles) have a mass of  -112110, 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  protonssaltsbondsisotopes.