Atomic Models and Electronic structure

• What did James Chadwick discover?

  The neutron
• Relative mass of a proton

  1
• Relative charge of a proton

  +1
• Relative mass of a neutron

  1
• Relative charge of a neutron

  0
• Relative mass of an electron

  1/1840
• Realive charge of an electron

  -1
• What is an isotope?

  Atoms of the same element with the same number of protons but different number of neutrons
• What does the atomic number tell us?

  The number of protons in an atom
• Define relative atomic mass

  Average mass of all isotopes of an element compared to 1/12 the mass of an atom of Carbon 12
• How many electrons do these shells contain?

  a)1s b)2p c)3s d)3d e) 4s

  a)2 electrons

  b)6 electrons

  c)2 electrons

  d)10 electrons

  e)2 electrons
• Does 3d or 4s have a higher energy orbital?

  3d
• What is an orbital?

  A region around the nucleus that can hold up to two electrons
• What would be the relationship between 2 electrons in the same orbital in terms of their spin?

  • Opposite spin
  • Repel each other as they are both negative
• Explain why chromium doesn't fit the trend for electronic conflagration?

  It only has one electron in its 4s orbital before filling the 3d

  
• Explain why copper doesn't fit the trend in electron configuration?

  It only has one electron in its 4s orbital before filling 3d

  
• What did John Dalton's atomic model suggest?

  • Atoms were solid invisible spheres
  • Elements were made from different spheres
• What did J.J Thomson atomic model suggest?

  • Plum pudding model
  • Atoms were a ball of positive charge
  • And has negative electrons embedded in it
• What did Rutherford's gold foil experiment show?

  • Alpha particles went straight though the gold
  • Because an atom is mostly empty space
• Why did some particles in Rutherford's experiment deflect straight back?

  • He suggested that most of the mass of an atom is located in the centre of an atom
  • A positively charged nucleus
• What does the Bohr model suggest?

  Electrons exist in fixed energy shells
• What led to the refined Bohr model?

  • Not all electrons in the shell have the same energy
  • The refined Bohr model includes sub-shells with different energies