https://padlet.com/askalathil/dtchyn7chxtlsk23 Democritus, Aristotle, Dalton, Thomson, Rutherford, Bohr, Chadwick, Heisenberg, and others! en-us 2020-12-04 14:52:13 UTC 2023-12-21 07:48:44 UTC hello@padlet.com https://padlet.net/icons/png/1f929.png askalathil https://padlet.com/askalathil/dtchyn7chxtlsk23/wish/987732879 Democritus made his contribution in 400 B.C.
he named atoms from the Greek word, "Atomos" meaning not to be cut and indivisible.

]]> 2020-12-04 14:54:14 UTC https://padlet.com/askalathil/dtchyn7chxtlsk23/wish/987732879 askalathil https://padlet.com/askalathil/dtchyn7chxtlsk23/wish/990675426 Aristotle made his contribution in 300 B.C. he thought all made of four elements: Earth, water, fire, and air. He also believed that matter had four properties: hot, cold, dry, and wet.]]> 2020-12-05 22:02:23 UTC https://padlet.com/askalathil/dtchyn7chxtlsk23/wish/990675426 askalathil https://padlet.com/askalathil/dtchyn7chxtlsk23/wish/990681124 Dalton made his contribution in 1803 he made the first theory since the "death of chemistry." He found out that all matter is made up of atoms. He found that they were too small to see. Dalton also figured out that all atoms of a given element are exactly alike and atoms of different elements are different. ]]> 2020-12-05 22:09:09 UTC https://padlet.com/askalathil/dtchyn7chxtlsk23/wish/990681124 askalathil https://padlet.com/askalathil/dtchyn7chxtlsk23/wish/990687094 Thomson made his contribution in 1897. Thomson contributed the idea that atoms are made up of even smaller particles. He discovered the electron. Thomson said that atoms are made from a positively charged substance with negatively charged electrons all around it like chocolate chips in a cookie or raisins in a pudding. ]]> 2020-12-05 22:16:47 UTC https://padlet.com/askalathil/dtchyn7chxtlsk23/wish/990687094 askalathil https://padlet.com/askalathil/dtchyn7chxtlsk23/wish/990689212 Rutherford made his contribution in 1908.
He disproved Thomson's theory. He discovered the nucleus. He thought that atoms had a small, dense, positively charged enter which he proved to be the nucleus. He also thought negatively charged particles (electrons) are scattered outside the nucleus at a distance not like chocolate chips in a cookie or raisins in a pudding. ]]> 2020-12-05 22:19:34 UTC https://padlet.com/askalathil/dtchyn7chxtlsk23/wish/990689212 askalathil https://padlet.com/askalathil/dtchyn7chxtlsk23/wish/990693776 Bohr made his contribution in 1913. He agreed with Rutherford and also believed that electrons orbit the nucleus like planets circle the sun. ]]> 2020-12-05 22:25:45 UTC https://padlet.com/askalathil/dtchyn7chxtlsk23/wish/990693776 askalathil https://padlet.com/askalathil/dtchyn7chxtlsk23/wish/990695254 Chadwick made his contribution in 1932. Chadwick played an important role in the history of the atom. He discovered a particle with no electric charge that make up a a nucleus with protons, neutrons. ]]> 2020-12-05 22:27:43 UTC https://padlet.com/askalathil/dtchyn7chxtlsk23/wish/990695254 askalathil https://padlet.com/askalathil/dtchyn7chxtlsk23/wish/990700028 These scientists made their contribution in the 20th Century. They disagreed with Bohr and instead agreed that electrons move in high speeds in an electron cloud around the nucleus. They said electrons spin around the nucleus billions of times in one second. They also believed that the electrons location depended on how much energy it had. ]]> 2020-12-05 22:34:26 UTC https://padlet.com/askalathil/dtchyn7chxtlsk23/wish/990700028