Chem- formation of ions

• Ions are charged particles——— they can be single atoms OR groups of atoms
• When atoms lose or gain electrons to form ions, they are trying to get a full outer shell——— {like a noble gas}
• when metals form ions, they lose electrons {from their outer shell} to form positive ions
• when non-metals form ions, they gain electrons {from their outer shell} to form negative ions
• • if an electron is lost the charge is positive
  • if an electron was gained the charge is negative
  • Eg. if 2 electrons is lost the charge is 2+, but if 3 electrons were gained, the charge is 3-
• Metals gain/lose electrons to form positive/negative ions (cations)

  Lose

  positive
• Non-metals gain/lose electrons to form positive/negative.

  Gain

  negative