Why do ionic substances only conduct electricity in solution, and why do metallic substances conduct?
Covalent bonds involve a shared electron pair between two atoms. However, this electron pair is not always shared equally between the two atoms. How the atoms are shared depends on the electronegativity of the two atoms involved. Possible sharing options range from the electrons being shared equally to the electrons being completely with one of the two atoms. I will list them in this order now: – Non-polar covalent (both electrons are shared equally between the two atoms) – Polar covalent (both electrons are pulled somewhat more towards one of the two atoms, creating a small difference in charge) – Ionic bond (both electrons are completely with one of the two atoms) Metal atoms in their solid state form a grid structure in which the electrons are shared between all atoms in the grid and are thus delocalised: they do not belong to one individual atom. For a substance to be a conduit, delocalised electrons are needed.
