Question

What causes dipole moment?

Answer 1

The difference in electronegativity between two bonded atoms.

Explanation:

The difference in electronegativity between two bonded atoms leads to shift of the electron density more toward the higher electronegative atom which will result in the creation of a partial negative charge on the more electronegative atom and a positive partial charge on the less electronegative atom. The presence of these oppositely charged entities next to each other will lead to the formation of the dipole moment.

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