Atomic structure and Periodic table

• Isotopes

  Atoms of the same element but have different neutrons
• Ions

  Atoms which have an overall charge
• Group 0 Nobles gases

  
  

  gases at room temperature

  full outer energy level

  unreactive
• When metals react they lose electrons to form positive ions.
• Group

  Number of electrons in outer shell
• Periods

  Number of shells
• Group 1 Alkali Metals

  Soft texture

  very reactive

  one electron in the outer shell

  they lose electron forming a one positive ion (+1)

  low melting and boiling point

  metals
• Group 7 Halogens

  non-metals

  high melting and boiling point

  seven electrons in the outershell

  less reactive

  they gain electron forming a one negative ion (-1)