Question

Which statement explains why a C–O bond is
more polar than a F–O bond?
(1) At STP, carbon has a greater density than
fluorine.
(2) A carbon atom has more valence electrons
than a fluorine atom.
(3) The difference in electronegativity between
carbon and oxygen is greater than that
between fluorine and oxygen.
(4) The difference in first ionization energy
between carbon and oxygen is greater than
that between fluorine and oxygen.

Answer 1

The correct answer is statement 3, the difference in electronegativity between carbon and oxygen is greater than that between fluorine and oxygen. The most polar bond is the one with the highest difference in electronegativity values between two atoms. In this case, the C-O bond.

Answer 2

Answer: (3) The difference in electronegativity between  carbon and oxygen is greater than that  between fluorine and oxygen.

Explanation: Polarity of a molecule is due to the difference in electronegativity of the atoms. More is the electronegativity difference, more is the polarity.

Electronegativity of carbon = 2.5

Electronegativity of oxygen = 3.5

Electronegativity of fluorine = 4.0

Thus the difference in electronegativity of carbon and oxygen is=(3.5-2.5)= 1.0

Thus the difference in electronegativity of fluorine and oxygen is=(4.0-3.5)= 0.5.

Thus C-O bond is more polar than F-O bond.