How does symmetry affect polarity

Enantiomers are non-superimposable mirror images of each other, and one consequence of this symmetrical relationship is that they rotate the plane of polarized light passing through them in opposite directions.

Such molecules are said to be chiral, 2 meaning that they cannot be superimposed on their mirror image. Such an axis is often implied by other symmetry elements present in a group. The polarity of a molecule defines its other physical properties such as melting point, boiling point , surface tension , vapor pressure etc. In simple terms, polarity occurs when the electron distribution in a molecule is asymmetric. This results in a net dipole moment in the molecule.

One end of the molecule is charged negative while the other gets a positive charge. The main reason for the polarity of a molecule is the electronegativity of the two atoms participating in the covalent bond. In covalent bonding, two atoms come together to share a pair of electrons. The shared pair of electrons belong to both the atoms.

However, the attractions of atoms towards the electrons differ from element to element. For an example oxygen shows more attraction towards electrons than hydrogen. This is called electronegativity. When the two atoms participating in forming the bond have electronegative difference 0. This results in a slight negative charge on the more electronegative atom, leaving a slight positive charge on the other.

In such cases, the molecule is considered to be polarized. Figure 1: Hydrogen fluoride molecule. The highly negative F in the HF molecule gets a slight negative charge while the H atom becomes slightly positive.

This results in a net dipole moment in a molecule. The polarization of a molecule greatly depends on the shape of the molecule. How do properties of ionic and molecular compounds differ? How do ionic and molecular compounds dissolve? How do ionic and molecular compounds compare in terms of physical properties? How do ionic and molecular compounds compare in terms of melting points?

How do ionic and molecular compounds achieve stability? How do ionic and molecular bonds differ? How do nonmetals bond?