Element & Periodic Table

• In the periodic table:

  1. Mass increases from left to right
  2. Mass increases downwards
• The smaller number is the atomic number which is basically the number of proton. The number of proton = the number of electron
• The bigger number is the mass number which is the sum of proton + neutron.
• Number of neutrons = Mass number - atomic number
• Group number (column) indicates the number of electrons in the outer most shell
• the period (row) indicates the number of electron shells