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Democritus
He said that everything is made up of atoms. The atoms are small and can not be broken up into smaller pieces. He figured this out by breaking up an object, it will get smaler and eventually you won't be able to break it up anymore. Coffey, Jerry. "Democritus Atom." Universe Today. N.p., 22 Mar. 2010. Web. 19 Feb. 2015. Dewitt, Tyler. "GaggleTube Video - Models of the Atom Timeline." GaggleTube Video - Models of the Atom Timeline. N.p., 6 Dec. 2012. Web. 19 Feb. 2015.
EasyBib -
Dalton
Dalton's model explained that atoms were tiny invisibly, indestructable particles; And that each had a certain mass, size, and chemical behavior that determined by what kind of element they were.
The method he use to make his discovery , he observed and used theories from observations.
He called his model the " Billiard Ball model" because he thought that atoms looked like billiard balls from pool. -
Period: to
Thomson
He discovered the electron by experimenting -
Thomoson
He discovered the electron.
He investigated the mysterious rays that happend when electricty passed through a salcrum.
He thhought the atom looked like a sphere embedded with electrons. The sphere had positive positive charges throughout it and negatively charged particles were also scattered across this model. -
Rutherford
Established the nuclear model of the atom. He became the first person to break up the nucleus of an atom Because of his many contributions to science he is often regarded as the father of nuclear science
He theorized atoms and that they are contructed the solar system.
His model showed that an atom has a positive center with orbiting electrons. The positively charged center Rutherford discovered was later named the nucleus. -
Bohr
Bohr's theory was based on an earlier one proposed by Rutherford He proposed that the electrons could travel only in certain successively larger orbits around the nucleus He thought the outer orbits could hold more electrons that the inner.
Bohr's theory published in 1913 was based on an earlier on an earlier one proposed by ernest Rutherford.
The bohr model shows the atom as a small positvely charged nucleus surrounded by orbiting electrons. -
Heisenberg and Schrodinger
Deveoloped a model of atomic nuclei which they are munch up of nuetrons and protons (Schrodinger equation) Deveoloped a mathematical equation describing the ware like behavior of atomic particles ( Schrodinger equation in 1925)
