https://padlet.com/amo20/i573un588eiq503f Historical developments over time for the creation of the atomic model en-us 2021-04-21 06:12:24 UTC 2025-04-23 16:29:27 UTC hello@padlet.com https://padlet.net/icons/png/1f469-1f52c.png https://padlet.com/amo20/i573un588eiq503f/wish/1444999461 Democritus, a Greek philosopher suggested the matter was made up of tiny, solid and unbreakable particles. These were called atomos meaning 'invisible']]> 2021-04-22 00:26:47 UTC https://padlet.com/amo20/i573un588eiq503f/wish/1444999461 https://padlet.com/amo20/i573un588eiq503f/wish/1445000738 The ancient Greeks believed that all matter was made up of only four fundamental elements; earth, fire, air and water. This was the basis continuum model, which predicted that regardless of the number of times you halve a piece of matter, it can always be broken down into smaller pieces.]]> 2021-04-22 00:27:16 UTC https://padlet.com/amo20/i573un588eiq503f/wish/1445000738 https://padlet.com/amo20/i573un588eiq503f/wish/1445001049 Electron Cloud Model

Scientist nowadays have come to the conclusion that the position of an atom can never be known. As it is impossible for electrons to revolve around the nucleus. Yet not in a specific shape that can be predicted. 
This is why it looks like a cloud!

It was rediscovered by Erwin Schrodinger. 

Renee, Gily, Sophie, and Eleanor]]> 2021-04-22 00:27:23 UTC https://padlet.com/amo20/i573un588eiq503f/wish/1445001049 https://padlet.com/amo20/i573un588eiq503f/wish/1445001159 James Chadwick discovered the neutron in 1932. This discovery showed that the nucleus was not just a positive charge it also had charge-neutral neutrons. Chadwick discovered this after he conducted an experiment in which he bombarded Beryllium with the natural radioactive decay of Polonium.]]> 2021-04-22 00:27:26 UTC https://padlet.com/amo20/i573un588eiq503f/wish/1445001159 https://padlet.com/amo20/i573un588eiq503f/wish/1445002114 The Hungarian philosopher, Philipp Lenard. Lenard described Atoms to be filled with fast moving particles he called 'dynamides'. These supposed dynamides were a neutrally charged particle that contains a heavy positive particle attached to a light negative particle. Lenard believed the atomic Mass of the atom was proportional to the number of dynamides present (therefore the number of dynamides was what formed the atom). Lenard's text results accurately proved that the solid matter in the atom was actually a very small portion of the enitre atom.  ]]> 2021-04-22 00:27:49 UTC https://padlet.com/amo20/i573un588eiq503f/wish/1445002114 https://padlet.com/amo20/i573un588eiq503f/wish/1445004315 Joseph John Thompson discovered the electron and its negative charge in 1897. Based on this he assumed there was also something to balanced the negative charge. In 1904 he validated this claim proposing the plum pudding model- a big ball of positive charge with electrons dotting through it.]]> 2021-04-22 00:28:38 UTC https://padlet.com/amo20/i573un588eiq503f/wish/1445004315 https://padlet.com/amo20/i573un588eiq503f/wish/1449655939 It was a previous model that was modified by a Danish scientist, Niels Bohr. He proposed that electrons are only able to travel around the nucleus calling them orbits. This resulted in the model being called the planetary model.

This model is different from our current understanding of an atom as the nucleus contains no neutrons and the electrons travel in set paths. ]]> 2021-04-22 22:57:16 UTC https://padlet.com/amo20/i573un588eiq503f/wish/1449655939 https://padlet.com/amo20/i573un588eiq503f/wish/1449659864 New Zealand scientist Ernest Rutherford performed a experiment in 1909, which lead to the discovery of the Nuclear Model in 1911. Rutherford fired a beam of positively charged alpha particles at gold foil and found that most particles went through the foil but some bounced back. This lead to the discovery that the mass of an atom is concentrated in a small positive nucleus which is surrounded by a large space with negative electrons.]]> 2021-04-22 22:59:24 UTC https://padlet.com/amo20/i573un588eiq503f/wish/1449659864 https://padlet.com/amo20/i573un588eiq503f/wish/1449663829 English Chemist John Dalton proposed experiments based on the atomic theory of matter, with elements and compounds. In Daltons theory, all matter is made up of hard invisible spheres. It introduced the existence of the electron and the notion of the atom being a divisible mass.

]]> 2021-04-22 23:01:44 UTC https://padlet.com/amo20/i573un588eiq503f/wish/1449663829