What Is a Nonpolar Bond?

In a molecule, the same kind of atom forms a covalent bond, and the two atoms have the same ability to attract electrons. The shared electron pair is not biased towards any one atom, so the bonding atoms are not significantly electric. Such a covalent bond is called a non-polar covalent bond , or a non-polar bond for short.

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Non-polar bond difference

A polar bond is a covalent bond formed by different kinds of atoms in a compound molecule. Because two atoms have different abilities to attract electrons, the shared electron pair must be biased to the atom with the stronger ability to attract electrons, so the atom with weaker electron attraction ability One is relatively positive. Such a covalent bond is called a polar covalent bond , or a polar bond for short .

When the atoms on the two sides of the electron pair are different, the attraction to the electrons will be different, which will bias the electron pair towards the electronegative atom. Formation of polarity. When the electrons on both sides of the atom are the same, the attraction of the electrons is the same, and the electrons do not bias which atom. Formation of non-polarity.

Method for distinguishing polar molecules from nonpolar molecules by nonpolar bonds

Criteria for non-polar molecules: central atom valence method and force analysis method

1. Central atomic valence method:

The composition is an ABn-type compound, and if the valence of the central atom A is equal to the ordinal number of the family, the compound is a non-polar molecule. For example: CH4, CCl4, SO3, PCl5

2. Force analysis method:

If the bond angle (or spatial structure) is known, force analysis can be performed, and those with a combined force of 0 are non-polar molecules, such as: CO2, C2H4, BF3

3. Diatomic molecules composed of the same kind of atoms are non-polar molecules.

Examples of non-polar bonds

1, NH3-the structure is a triangular pyramid, the electrical properties between each NH bond cannot be offset. It is that the electrons are biased to N, and the structure of NH3 is not symmetrical, so the electrical properties cannot be offset, so it is a polar molecule .

2. CO2-Although the electron pairs of CO are biased, because the structure of CO2 is linear and symmetrical, the electrical properties of the biased electrons are canceled out, thereby forming non-polar molecules.