Model of the atom GapFill

All matter is made up of  energyionsatomscells, which come in different types, called  particleselementsatomsreactants, represented using symbols which can be found on the  compound sequenceInternetreactivity listperiodic table. When these react together,  beta particlesatomscompoundsmixtures are formed, which have formulae to show the  ratiopositionpercentageimportance of each element.  MixturesNeutronsElectronsPure substances contain multiple elements or compounds, and can be  shapedmeltedreactedseparated using filtration, distillation, crystallisation and chromatography.

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

• the  dough ballplum puddingupside-down pineappledoughnut model, where the atom is a ball of positive charge with electrons dotted around
• Rutherford's model - the  nuclearelectronicdirectionalconnective model - based on the observations of  beta particlealpha particlemetallicgamma particle scattering
•  Isaac NewtonMarie CurieNiels BohrNeil Armstrong's model, where electrons orbit the nucleus
•  Charles DarwinDmitri MendeleevJames ChadwickJames Dalton's model, where neutrons are also in the nucleus

Different  magneticalphainfraredsubatomic 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  protonssaltsisotopesbonds.