Question

Molecules that do not have positive and negative sides (no dipole movement symmetry)

Answer 1

Nonpolar molecules have no dipole moment due to their symmetrical charge distribution, while polar molecules have a dipole moment due to an asymmetrical charge distribution.

Step-by-step explanation:

Molecules that have no positive and negative sides, meaning they do not have a dipole moment, are known as nonpolar molecules. These molecules are symmetrical and typically contain no unshared pairs of electrons, which allows for the symmetry in their electron density and charge distribution. For instance, molecules like methane (CH4) and carbon dioxide (CO2) are nonpolar because they have a symmetrical structure leading to an even distribution of charge. A dipole moment occurs in polar molecules where there is an uneven distribution of electron density across the molecule, leading to a molecule having a partial positive charge on one end (delta positive or 8+) and a partial negative charge on the other end (delta negative or 8-). This is frequently due to differences in electronegativity between the atoms in the molecule or the presence of unshared electron pairs.

Answer 2

The distinction between polar and nonpolar molecules lies in their symmetry and the distribution of electron density. Nonpolar molecules have symmetric structures with no net dipole moment, while polar molecules have an asymmetric structure with a separation of charge, known as a dipole.

Explanition

Distinction between polar and nonpolar molecules

Molecules can be categorized as nonpolar or polar based on their symmetry and the distribution of charges. Nonpolar molecules are characterized by their symmetrical structure with no unshared pairs of electrons, which results in an even distribution of electron density across the molecule. This means that nonpolar molecules do not have a net dipole moment because the individual bond dipoles, if any, cancel each other out due to the molecule's symmetry.

On the other hand, polar molecules display an asymmetric structure that results in an uneven distribution of electron density. This is often due to the presence of lone pairs of electrons on a central atom or the bonding of atoms with differing electronegativities. Consequently, one end of a polar molecule may have a partial negative charge (often denoted as Δ8-) while the other end has a partial positive charge (Δ8+), qualifying the molecule as a dipole with two poles: a positive and a negative pole.

Examples of nonpolar molecules include methane (CH4) and carbon tetrachloride (CCl4), which have symmetrical shapes (tetrahedral and tetrahedral, respectively). Examples of polar molecules are water (H2O) and ammonia (NH3), which have bent and trigonal pyramidal shapes, respectively, leading to a net dipole moment.