Covalent is stronger because the 2 atoms involve share 2 or more outer shell electrons. Covalent bonds hold all of your biomolecules together. Ionic bonds are formed when a valence outer shell electron is transferred from one atom to another - a much weaker interaction.
An atom that shares one or more of its electrons will complete its outer shell. Covalent bonds are strong - a lot of energy is needed to break them. ... Both nuclei are strongly attracted to the shared pair of electrons in the covalent bond, so covalent bonds are very strong and require a lot of energy to break.
