IB Chemistry - Bonding

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Ionic bonding takes place between metal and non-metal atoms. The basic process involves several steps:

  • Transfer of electrons from metal to non-metal atoms to fulfill the octet rule
  • Formation of full outer shells.
  • Ion produced
  • Electrostatic attraction between oppositely charged ions
  • Giant lattice formation
Syllabus reference

Structure 2.1.1 - When metal atoms lose electrons, they form positive ions called cations. When non-metal atoms gain electrons, they form negative ions called anions.

  • Predict the charge of an ion from the electron configuration of the atom.


  • The formation of ions with different charges from a transition element should be included.

Tools and links

  • Structure 3.1 - How does the position of an element in the periodic table relate to the charge of its ion(s)?
  • AHL Structure 1.3 - How does the trend in successive ionization energies of transition elements explain their variable oxidation states?

In Chapter 2.60