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John Dalton
John Dalton contributed in the atomic theory "Atomic theory is a scientific theory of the nature of matter, which states that matter is composed of discrete units called atoms, as opposed to the earlier concept which held that matter could be divided into any arbitrarily small quantity."
"Atomic Theory." Wikipedia. Wikimedia Foundation, 09 Mar. 2013. Web. 03 Sept. 2013.
"John Dalton." Wikipedia. Wikimedia Foundation, 09 Feb. 2013. Web. 03 Sept. 2013. -
Dalton's model
The theory of the Dalton's model was based that the atoms of different elements could be recognized by how much they wiegh. Eventhough It was not so accurate because he made a mistake in believing that the simplest compound of two elements are formed from atoms of each element in a 1:1 ratio, and for example he gave oxygen an atomic weight of seven instead of eight,
"Dalton Atomic Theory." Dalton Atomic Theory. N.p., n.d. Web. 03 Sept. 2013. -
William Crooke
Discovered that the cathode rays had really different properties, for example it travel straight in a line,also they cause pinwheels in their path to spin indicating they have mass and betweeen other properties.
"Atomic Structure Timeline." Atomic Structure Timeline. N.p., n.d. Web. 02 Sept. 2013. -
JJ Thomson
JJ Thomson in 1897 discovered the existence of the electron while he was testing other experiments.
"Joseph John Thomson." Homepage of the Chemical Heritage Foundation. N.p., n.d. Web. 02 Sept. 2013. -
Ernest Rutherford
He discovered the nucleus of a atom on gold, while he did the Gold Foil Expertiment is series of tests in which positively charged alpha particles were fired with a thin sheet of gold foil.
"Ernest Rutherford." Wikipedia. Wikimedia Foundation, 09 Feb. 2013. Web. 02 Sept. 2013. -
Plum Pudding Atomic Model
Was proposed by JJ Thomson, and it said that the atom is composed of electrons surrounded by positive charge and to balance the electrons' it had negative charges, like negatively charged "plums" surrounded by positively charged "pudding". This is were the name plum pudding comes from.
"Plum Pudding Model." Wikipedia. Wikimedia Foundation, 30 Aug. 2013. Web. 03 Sept. 2013. -
Rutherford Model
In 1909 Ernest Rutherford made an experimetn where he examined the gold foil with alpha particles (Helium nuclei). A source which alpha decay is placed in a lead box with a small hole in it. After this any of the alpha particles which hit the inside of the box are simply stopped by the box. Only those which pass through are the ones who get out of the box meaning that they are able tofollow a straight line to the gold foil.
"The Rutherford Model." The Rutherford Model. N.p., n.d. Web. 03 Sept -
Bohr Model
This model proposed by Niels Bohr was not fully correct but it helped in the future. This model stated that the electrons and neurons had a nucleus, and the electrons orbit the nuclues. This is why they compare this model with the orbit of the sun becuase the neurons orbit the nuclues.( it of course the nucleus has a much smaller ratio than the sun)
Citation added:
"The Bohr Model." The Bohr Model. N.p., n.d. Web. 03 Sept. 2013.
http://csep10.phys.utk.edu/astr162/lect/light/bohr.html -
Niels Bohr
Made a major contribution in the understanding atomic structure and quantum mechanics
Citation added:
"Niels Bohr." Wikipedia. Wikimedia Foundation, 09 Mar. 2013. Web. 03 Sept. 2013. -
Quantum Mechanical Model
This model was constructed by Erwin Schrödinger. . It is a model that is compared with the Bohr's model. The quantum mechanical model shows that electrons don’t have set orbital but are in random motion captured within the areas of electron probability distribution. The quantum mechanical model advantage is that it works for all the elements and in bohr only works for hydrogen.
"ATOMIC STRUCTURE." ATOMIC STRUCTURE. N.p., n.d. Web. 03 Sept. 2013. -
James Chadwick
Discovered the Neutron in an Atom .
"James Chadwick." Wikipedia. Wikimedia Foundation, 09 Mar. 2013. Web. 03 Sept. 2013.
