periodic table

• what did John Dalton discover?

  Atom- a tiny sphere- 1803
• what did JJ Thompson discover?

  electrons- 1897
• what did Ernest Rutherford discover?

  nucleus and protons (gold foil experiment)- 1911
• what did Neils Bohr discover?

  energy levels/ electron shells- 1913
• what did James Chadwick discover?

  neutron- 1932
• who created the 1st periodic table?

  John Dalton
• What did Dalton list elements in order of?

  increasing by mass
• Newlands' table


  2nd periodic table created- properties repeated every 8 elements
• Mendeleev's periodic table


  3rd (most praised) periodic table created- grouped by property and left gaps for undiscovered elements
• Why was Mendeleev's periodic able significant?

  he predicted atoms before they existed
• modern periodic table


  ordered by atomic number

  grouped by property