Is I2 Polar or Nonpolar?

Why is I2 Nonpolar?

Iodine exists as a diatomic molecule with two identical iodine atoms bonded by a single covalent bond. Since both atoms have the same electronegativity (2.66), no partial charges form and the dipole moment is 0 D, making I2 a nonpolar molecule.

• Symmetric linear geometry (180°): The atoms are arranged symmetrically around the central atom. This forces all bond dipoles to point in directions that cancel each other out exactly.
• Weak bond polarity: The small electronegativity difference (0.00) between I and I produces only weakly polar bonds, and the symmetric geometry cancels even these.
• Zero net dipole (0 D): Because all bond dipoles cancel, the net dipole moment is 0 D. Any molecule with zero net dipole moment is classified as nonpolar.

Molecular Geometry of I2

I2 has a linear molecular geometry with a bond angle of 180°. Here is why this shape determines polarity:

• The linear arrangement places all outer atoms at equal angles (180°) from the central atom, creating perfect spatial symmetry.
• Each bond dipole has an equal and opposite counterpart — they cancel in pairs, leaving no net charge separation.
• Symmetry is the key: even if the individual bonds are polar, the linear geometry ensures a net dipole of 0 D.

Electronegativity and Polarity

Electronegativity measures how strongly an atom attracts bonding electrons. A difference greater than ~0.5 on the Pauling scale generally means the bond is polar.

In I2:

• I (central atom) electronegativity: 2.66
• I (outer atom) electronegativity: 2.66
• Difference: 0.00 — below the ~0.5 threshold, so the I–I bonds are only weakly polar

With a small electronegativity difference (0.00) and a symmetric linear geometry, I2 is nonpolar with a net dipole of 0 D.

Is I2 Polar or Nonpolar? (Quick Answer)

I2 (Iodine) is nonpolar. I2 is a nonpolar molecule because both iodine atoms are identical and share electrons equally, producing no net dipole.