Atomic Model Timeline

  • 460

    Democritus Atomic Model

    Democritus Atomic Model
    Democritus was anancient philospoher. He lived from 460 BC to 370 BC. Democritus felt that atoms were mechanically bounded.He felt his atoms could not be seperated.Democritus said that atoms are indestrucible, solid but invisible and are also homegenous.
  • Dalton's Atomic Theory

    Dalton's Atomic Theory
    Dalton was an English chemist. Dalton's theory was that all matter is made up of atoms. Atoms are indivisible and indestructible. Atoms with a given element are identical in mass and properties. Compounds are formed by a combination of two or more different kinds of atoms. And chemical reactions are rearrangement of atoms. Dalton's theory still remains valid.
  • Neil Bohr's Theory

    Neil Bohr's Theory
    Bohr was a student of Rutherford's and felt that his theory needed improvement. Bohr thought that atoms were small, with positive charges and move in circular orbits around the nucleus. Bohr's theory imporoved the cubic model, plum-pudding model, Saturnian model, and the Rutherford model. Bohr discovered that there are different energy levels. when the electrons are given high energy it goes up and when it gives low energy it goes down.
  • Periodic Table

    Periodic Table
    The periodic table was created by Dmitri Mendeleev during 1869. Periodic table was created to state the properties of elements that are arranged by atomic number. The periodic table is still used in todays science.
  • Eugen Goldstein

    Eugen Goldstein
    Eugen was a German physicist. His experiments were done with cathode ray tubes. Eugen discovered that atoms have positive charge. He found that the cathode rays emitted from a metal surface and carried energy. He later died in 1930.
  • Thomson

    Thomson
    Joseph John was born on 1856.At the age of 14, Thomson's parents enrolled him as an apprentice engineer.Thomson is known for discovering electrons and isotopes and inventing the mass spectrometer. Thomson's work has been awarded because he discovered electrons and the electricity in gases.
  • Rutherford's Atomic Model

    Rutherford's Atomic Model
    Rutherford model is an model of the atom. He analyzed that J.J Thomson's model that was called "plum pludding model" was incorrect. He came up with the region which he called the nucleus. Rutherford created his gold-foil experiment. Rutherford thought that electrons in the atom just float freely but that wasnt the case.
  • James Chadwick

    James Chadwick
    Chadwick graduated from college and later started working under Rutherford. During 1932, Chadwick discovered the existence of neutrons. Chadwick discovered that neutrons are particles of electrical charge. Chadwick worked towards the creation of the atomic bomb!
  • Atomic bombing of Nagasaki and Hirsoshima

    Atomic bombing of Nagasaki and Hirsoshima
    On August 6,1945 during WW11 the bomd landed on the Japanese lands. It was the first deployed atomic bomb. This bomb killedmany and many of people. It was known to be the most cruel bomb. These to bomb attacks represent the only two nuclear weapons in war.It was a emorable day for the Japanese people and land.