Formation of ions

• What is an ion?


  A charged particle.
• When atoms lose or gain electrons to form ions, they’re trying to get a full outer shell.
• How do metals ionise?


  They lose electrons to form positive ions.
• How do non metals ionise?


  They gain electrons to form negative ions.
• The number of electrons lost or gained is the same as the charge on the ion.
• Which element groups most readily form ions?


  1,2,6,7.
• Group 1 and 2 elements are metals and they lose electrons to form positive ions (cations).
• Group 6 and 7 elements are non-metals and they gain electrons to form negative ions (anions).
• Elements in the same group form ions with the same charges.