https://padlet.com/stellapittsqz/4rnylqi0f4ps6t04 group 2 en-us 2020-10-26 20:47:58 UTC 2026-03-06 19:02:46 UTC hello@padlet.com https://padlet.com/stellapittsqz/4rnylqi0f4ps6t04/wish/863590018 Democritus's theory was that if you kept cutting something in half, it would eventually reach the state of atomos, which meant uncuttable in his language. This eventually led to the naming of atoms. He also came up with the theory that atoms were indestructible, and that they are always in motion.]]> 2020-10-26 20:51:31 UTC https://padlet.com/stellapittsqz/4rnylqi0f4ps6t04/wish/863590018 charlesweatherby9f https://padlet.com/stellapittsqz/4rnylqi0f4ps6t04/wish/863590503 John Dalton proposed the theory that all matter was composed of atoms, and that they were indivisible and indestructible building blocks. He proposed that all atoms were identical, but they had different sizes and mass depending on the element.]]> 2020-10-26 20:51:42 UTC https://padlet.com/stellapittsqz/4rnylqi0f4ps6t04/wish/863590503 charlesweatherby9f https://padlet.com/stellapittsqz/4rnylqi0f4ps6t04/wish/863591290 In 1897, JJ Thompson discovered the electron using a cathode ray tube. He would shoot the cathode ray through the tube and he added a battery on each side, one with a positive charge and one with a negative, and the ray was attracted to the negative side with all elements he did the experiment with, so he knew that there was a smaller, negative charged particle in the atom.]]> 2020-10-26 20:51:59 UTC https://padlet.com/stellapittsqz/4rnylqi0f4ps6t04/wish/863591290 https://padlet.com/stellapittsqz/4rnylqi0f4ps6t04/wish/863591339 In 1904, J.J Thompson proposed the idea of the Plum Pudding Atomic Model. The model was referred to as "Plum Pudding" because it had negatively charged electrons, or plums, that were dispersed throughout the positively charged space in the atom, or pudding.]]> 2020-10-26 20:52:00 UTC https://padlet.com/stellapittsqz/4rnylqi0f4ps6t04/wish/863591339 https://padlet.com/stellapittsqz/4rnylqi0f4ps6t04/wish/863592590 in 1911, this Nuclear Atomic Model was discovered by Ernest Rutherford. This model proved J.J Thompsons previous "Plum Pudding Model" wrong, showing there was a centralized positive volume, or the Nucleus. Because of his discovery, this model is also known as the "Rutherford Model".]]> 2020-10-26 20:52:30 UTC https://padlet.com/stellapittsqz/4rnylqi0f4ps6t04/wish/863592590 stellapittsqz https://padlet.com/stellapittsqz/4rnylqi0f4ps6t04/wish/863592679 Niels Bohr proposed that electrons circled the nucleus in three levels of "rings." This model is very simple and although it isn't 100% accurate, people still use it today because it is easily understood.]]> 2020-10-26 20:52:31 UTC https://padlet.com/stellapittsqz/4rnylqi0f4ps6t04/wish/863592679 stellapittsqz https://padlet.com/stellapittsqz/4rnylqi0f4ps6t04/wish/863593879 Proposed by Erwin Schrödinger who proves that electrons do not circle the neutron in simple rings and that there is no way to pinpoint exactly where and electron is at any given point. This is more accurate the Bohr model, in which quantization was assumed with no mathematical basis.

]]> 2020-10-26 20:52:59 UTC https://padlet.com/stellapittsqz/4rnylqi0f4ps6t04/wish/863593879 https://padlet.com/stellapittsqz/4rnylqi0f4ps6t04/wish/863594008 In 1909, Robert Millikan and Harvey Fletcher conducted their "Oil Drop Experiment" and found that the charge of an electron was negative. The "Oil Drop Experiment" used an electric field to counteract the falling of a drop of oil due to gravity. ]]> 2020-10-26 20:53:03 UTC https://padlet.com/stellapittsqz/4rnylqi0f4ps6t04/wish/863594008 stellapittsqz https://padlet.com/stellapittsqz/4rnylqi0f4ps6t04/wish/863594514 James Chadwick discovered the neutron in a 2 week long experiment. He was fascinated by an earlier experiment in which paraffin wax was bombarded with Beryllium and found that the wax ejected radiation. Chadwick held some experiments very similar to this and found evidence that the radiation was the neutron instead of gamma radiation, which is what was previously thought.]]> 2020-10-26 20:53:15 UTC https://padlet.com/stellapittsqz/4rnylqi0f4ps6t04/wish/863594514