Scientists developed a theory to explain ionic bonding before they developed a theory to explain covalent bonding. What aspect of covalent bonds most likely prompted scientists to find a new theory of bonding?
Select one:
a. Covalent bonds do not involve metals.
b. Covalent bonds do not form crystals.
c. Covalent bonds involve valence electrons.
d. Covalent bonds do not involve atoms with opposite charges.