The molecule which has zero dipole moment is?

• A. CH₂Cl₂
• B. BF₃
• C. NF₃
• D. ClO₂

The molecule that has a zero dipole moment is BF₃ (Boron Trifluoride). This occurs because the molecule has a symmetrical trigonal planar shape, which allows the dipole moments of the three B-F bonds to cancel each other out.

Understanding Molecular Geometry

Molecular geometry plays a crucial role in determining the dipole moment of a molecule. In the case of BF₃:

• Symmetry: The symmetrical arrangement of the fluorine atoms around the boron atom leads to a balanced distribution of charge.
• Electronegativity: Although fluorine is highly electronegative, the symmetrical shape ensures that the overall dipole moment is zero.

Comparison with Other Options

Let’s briefly look at the other molecules:

• CH₂Cl₂: This molecule has a net dipole moment due to its asymmetrical shape.
• NF₃: Although it has a trigonal pyramidal shape, it has a dipole moment because of the lone pair on nitrogen.
• ClO₂: This molecule is bent, leading to a non-zero dipole moment.

In summary, BF₃ is the only molecule among the options provided that exhibits no dipole moment due to its symmetrical structure.