Development of the nuclear model of the atom

• Alpha scattering experiment observations


  most of the particles went through

  some went through but were deflected

  few bounced back
• observation 1

  most of the atom is empty space
• observation 2

  part fo the atom has a positive charge
• observaton 3

  mass and charge of the atom is concentrated in one place
• 1 = electron

  2= positively charged nucleus

  
• niels bohr proved that electrons orbit the nucleus at specific distances from the nucleus in orbits that are called shells
• positive charge of any nucleus is divided between a whole number of smaller positively charged particles called protons

  
• reasons for the discovery of neutrons

  -protons having the same charge would repel each other

  -there was a difference between an atoms atomic number and atomic mass
• 1 = electron

  2= positively charged sphere