The molecule shown here is difluoromethane 1CH2F22, which is used as a refrigerant called R-32. (c) If the molecule is polar, which of the following describes the direction of the overall dipole moment vector in the molecule: (i) from the carbon atom toward a fluorine atom, (ii) from the carbon atom to a point midway between the fluorine atoms, (iii) from the carbon atom to a point midway between the hydrogen atoms, or (iv) from the carbon atom toward a hydrogen atom?

Key Concepts

Molecular Polarity

Molecular polarity arises from the distribution of electrical charge across a molecule. A molecule is polar if it has a net dipole moment due to differences in electronegativity between atoms, leading to uneven charge distribution. In difluoromethane, the fluorine atoms are more electronegative than carbon and hydrogen, creating a dipole moment that points toward the fluorine atoms.

Dipole Moment

The dipole moment is a vector quantity that represents the separation of positive and negative charges in a molecule. It is defined as the product of the charge and the distance between the charges. In the case of difluoromethane, the dipole moment vector points from the carbon atom toward the more electronegative fluorine atoms, indicating the direction of the overall charge distribution.

Electronegativity

Electronegativity is a measure of an atom's ability to attract and hold onto electrons within a chemical bond. In difluoromethane, fluorine has a significantly higher electronegativity than carbon and hydrogen, which influences the molecule's polarity. This difference in electronegativity leads to the formation of polar bonds, contributing to the overall dipole moment of the molecule.