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John Dalton's theory
Democritus first sugg. the existence of the atom but it took almost two millennia before Dalton came up with five main points to his discovery which are 1.Everything is made out of atoms and they cant be changed, destroyed, or created. 2.compounds have to do with two or more different atoms put together. 3.All atoms of a given element are similar in weight and properties. 4.all chemical reactions involves atoms being arranged, combined, and separated. 5.elements are made of tiny particles,atoms -
Period: to
Atomic model timeline
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JJ Thompson- cathode ray experiment
Thomson, in 1897, was the first to suggest that the fundamental unit was over 1000 times smaller than an atom, suggesting the subatomic particles now known as electrons. Using the cathode ray tube, J J Thompson was able to observe streams of electrons which led him to believe that there are both positive and negative forces at work inside the atom.which later leads him to the "plum pudding" model -
JJ Thompson- "plum pudding" model
JJ Thompson was the first to develp the first model of an atom he thought that The 'Plum Pudding' model of the atom was described as this, Negatively charged electrons (the plums) are embedded in a sphere of uniform positive charge (the pudding). -
Ernest Rutherfords theory/Model
Ernest Rutherford created a model of the atom. Using his gold-foil experiment and found out that there is a small nucleus in the atom. He also discovered that the electrons, in the atom, floated freely around in an electron cloud. -
Neil Bohr's Theory/Model
Neil Bohr took the quantum theory and applied it to Rutherford's theory. Instead of having electrons floating around, he discovered that there are different energy levels. when given more enery, The electrons will move up to a higher Energy level and when given off less energy, The electrons go down an energy level. figuring out that electrons cant stay in beteween energy levels. The electrons move in circular orbits at fixed distances from the nucleus ,showing that Ruthefords theory was wrong. -
Erwin Schrödinger Quantum Mechanical theory/Model
Erwin Schrödinger Developed mathematical equations to describe the motion of electrons in atoms which led to his theory and electron cloud model.Edwin Schrodinger stated that rather than electrons being distributed within an electron configuration of shells and energy levels, they were arranged in orbitals which were systematically distributed within Electron Clouds. Orbit = space that surrounds a nucleus in which two electrons may randomly move. -
Aomic bombs in the WWII
The US dropped atomic bombs on Hiroshima and Nagasaki and thats what made Japan surrender to the US and its allies, ending WWII. There has been conflict over this weapon ever since that event. The atomic bomb contains a neutron in the plotonium nucleus. the plutonium itself is unstable and radioactive because its atoms are constatnly falling apart. every time the atoms break up into smaller and stable parts, it releases off more energy. that energy is what becomes the radiation.
