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The Atom Models
This will show you when and why the atom's models changed over time. As technology got more advanced, they were able to make more accurate models. -
John Dalton
English chemist, meteorologist and physicist. He is best known for his pioneering work in the development of modern atomic theory, and his research into colour blindness. -
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John Dalton's Model
Dalton’s atomic model is one of the fundamentals of physics and chemistry. This theory of atomic composition was hypothesized and partially confirmed by the English chemist and Physicist John Dalton. Dalton came with his Atomic theory as a result of his research into gases. He discovered that certain gases only could be combined in certain proportions even if two different compounds shared the same common element or group of elements. Through deductive reasoning and experimentation, he made an i -
J.J. Thomson
British physicist and Nobel laureate. He is credited with discovering electrons and isotopes, and inventing the mass spectrometer. -
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J.J Thomson
J. J. Thomson considered that the structure of an atom is something like a raisin bread, so that his atomic model is sometimes called the raisin bread model. He assumed that the basic body of an atom is a spherical object containing N electrons confined in homogeneous jellylike but relatively massive positive charge distribution whose total charge cancels that of the N electrons. The schematic drawing of this model is shown in the following figure. Thomson's model is sometimes dubbed a plum pudd -
Hantaro Nagaoka
Japanese physicist and a pioneer of Japanese physics during the early Meiji period. -
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Hantaro Nagaoka's Model
Nagaoka developed a planetary model of the atom.[2] The model was based around an analogy to the explanation of the stability of the Saturn rings (the rings are stable because the planet they orbit is very, very massive). The model made two predictions:
A very massive nucleus (in analogy to a very massive planet)
Electrons revolving around the nucleus, bound by electrostatic forces (in analogy to the rings revolving around Saturn, bound by gravitational forces). -
Rutherford Model
New Zealand-born British chemist and physicist who became known as the father of nuclear physics. -
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Rutherford's Model
Rutherford developed the planetary model of the atom, which put all the protons in the nucleus and the electrons orbited around the nucleus like planets around the sun. -
Niel’s Bohr
Niels Henrik David Bohr was a Danish physicist who made foundational contributions to understanding atomic structure and quantum mechanics, for which he received the Nobel Prize in Physics in 1922. -
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Bohr's Model
The Bohr Model is an approximation to quantum mechanics that has the virtue of being much simpler. It is very similar to Rutherford's, but simplified. -
Louis de Broglie
Louis-Victor-Pierre-Raymond, 7th duc de Broglie, was a French physicist and a Nobel laureate in 1929. -
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Louis de Broglie's Model
proposed in 1924 that electrons could behave as waves under some conditions, a finding that helped scientists understand that the atom didn't behave like the solar system because electrons do not move in regular orbits. -
Erwin Schrodinger
Erwin Rudolf Josef Alexander Schrödinger, was an Austrian physicist who developed a number of fundamental results in the field of quantum theory, which formed the basis of wave mechanics. He also got a Nobel Prize. -
James Chadwick
Sir James Chadwick CH FRS was an English Nobel laureate in physics awarded for his discovery of the neutron. Chadwick studied at the University of Manchester and the University of Cambridge. -
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James Chadwick's Model
In 1932 the English physicist James Chadwick discovered the neutron. He found it to measure slightly heavier than the proton with a mass of 1,840 electrons and with no charge (neutral). The proton-neutron together, received the name, "nucleon."
The existence of neutrons explained why atoms are heavier than the total mass of their protons and electrons.
So, basically, the neutron was added to the nucleus.
