Atomic Structure through the ages

By tanyaa23
  • 1932 BCE

    James Chadwick

    Nucleus contained particles called neutrons, which are of neutral charge, and electrons, of positive charge. Neutrons are as heavy as protons.
  • 1913 BCE

    Neil Bohr

    There is a specific number of electrons in each orbit around the nucleus. These orbits have different energy levels which determine chemical properties.
  • 1911 BCE

    Ernest Rutherford

    Identified that atoms contain a nucleus which are positively charged. Negatively charged atoms orbited this nucleus.
  • 1897 BCE

    J.J. Thompson

    Plum pudding model. Negative electrons are in a sea of positively charged electrons.
  • 1808 BCE

    John Dalton

    All matter consists of tiny particles called atoms which are invisible and indestructible. Compounds are formed by joining atoms of two or more different elements. Atoms of the same elements are alike. Dalton’s model was like a hard invisible ball.