What characteristic of the molecule is important for this ""force"" to be effective in bonding?

Intermolecular forces: forces attracting one molecule to its neighbors.

Explanation:

Hello,

Bonds are formed when two molecules are interacting (crashing or attracting to each other) and they are allowed to get joined via their valence electrons since we're talking about bonds. Those forces are called intermolecular forces as long as the molecules have charges that could attract or repeal another molecule (neighbors), of course, as we're considering bonds, we talk about attractive forces, making the bonding to be effective.

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