Chemical Bonds Chemistry

Question

Which one of the chemical bonds listed below is the strongest? Which bond is the weakest?

Explain your answers. (8)

• the ionic bonding in NaCl EN Values

• the ionic bonding in FeCl3 N = 3.0

• an O=O double bond O = 3.5

• a N=O single bond F = 4.0

• a N–F single bond

Answer 1

First, to be technically correct, there really is no such thing as a purely ionic or purely covalent bond, but with that caveat aside, we'll proceed.

For intramolecular forces/bonds, the strength is generally agreed to be metallic > ionic > polar covalent > nonpolar covalent.

NaCl and FeCl₃ are the two ionic compounds. The strongest bonds would exist in FeCl₃, and then NaCl.

For the covalent bonds, using EN values to "guestimate" the most polar to least polar, we would have

N-F > N-O > O=O (note your questions states that the N-O is a single bond even though it is shown as a double bond). So, this would also be the bond strength order. So, in summary, remembering that this is all relative and not absolute, we would have the following order from strongest to weakest:

FeCl₃ > NaCl > NF > N-O > O=O