Question

Which of the following molecules has "NON ZERO" dipole moment value?

• A. CCl₄
• B. HI
• C. CO₂
• D. BF₃

Answer 1

The Correct Option is B

A molecule exhibits a non-zero dipole moment if there's charge separation due to electronegativity differences between bonded atoms, and its molecular geometry does not cause these individual bond dipoles to cancel.

CCl₄: Carbon tetrachloride possesses a tetrahedral geometry. Despite the polarity of the C-Cl bonds, the symmetrical arrangement of the four chlorine atoms around the central carbon atom results in the cancellation of the bond dipoles, yielding a net zero dipole moment.

HI: Hydrogen iodide is a diatomic molecule. Iodine exhibits greater electronegativity than hydrogen, forming a polar bond and a net dipole moment directed towards the iodine atom. As a diatomic molecule, no other bond dipoles are present to counteract this.

CO₂: Carbon dioxide has a linear geometry. The C=O bonds are polar; however, the molecule's symmetry causes the bond dipoles to cancel, resulting in a zero net dipole moment.

BF₃: Boron trifluoride features a trigonal planar geometry. The B-F bonds are polar, but their symmetric placement around the central boron atom leads to the cancellation of the bond dipoles, consequently producing a net zero dipole moment.