Democritus was an ancient Greek philosopher, the exact details from his birth are not known but it is estimated to be born sometime around 450 BC in Abdera, Greece. It is believed that he was the scientist to create the first atomic theory (Coffey, 2010). He claimed that absolutely everything is made up from atoms and that the atom is was the smallest particle of matter (Bennett, 2012). He also stated that atoms are physically indivisible and indestructible they have been and always will be, there are infinite number of atoms and this number will never change (Coffey, 2010). At the time he lived the technology of today was not available. He did not have electricity, microscopes and the internet (Bennett, 2012).
John Dalton was an English chemist born in 1766 and died in 1844. No drastic changes took place in the atomic theory for almost 2000 years. Scientists were still researching Democritus theory trying to build upon it …show more content…
Rutherford was the physicist who discovered the nucleus in the atom(Bio, 2013). In 1911 Rutherford conducted his main experiment; he shot positively charged alpha particles at a sheet of gold foil. At this point in time it was assumed that atoms ultimately had an overall positive charge. The expected results were that the particles would travel right through the gold foil. Although this was not the case, actually some of the alpha particles were deflected and others bounced right off. The main point this experiment proved that all of the positive charge had to be connected in the centre of the atom, which is now known as the nucleus (Bennett, 2012). After his discovery Rutherford changed the overall design of the model atom, instead of showing a diffuse overall positive charge he showed the positive charge located in the nucleus. His model is also commonly known as the planetary model because the placements of the electrons were thought to orbit the nucleus, much like the plants orbit the sun (Bennett,