Formation of Ions

• An Ion is a charged particle.
• Atoms gain and lose electrons to form ions in order to become more stable.
• The group number tells us how many electrons atoms have in their outermost shell
• Losing electrons requires energy, so group 1 and 2 atoms are more likely to form ions as it requires less energy.
• losing an electron creates a positive charge whereas gaining once creates a negative charge
• To use an equation to show the gain or loss of electrons we could present it like this:

  Loss- Na --> Na+ + e-

  Gain- Cl + e- --> Cl-