1.3 Chemical Bond: Molecular Polarity

Question 1

What is a polar molecule?

Answer 1

A polar molecule is one that has an uneven distribution of electrons, meaning one end of the molecule is slightly positive while the other end is slightly negative. The two electrically charged regions at each end of the molecule are called poles, and a molecule with two poles is referred to as a dipole.

This occurs due to the difference in electronegativity between the atoms that make up the molecule.

Question 2

What is a nonpolar molecule?

Answer 2

A nonpolar molecule is one that has an even distribution of electrons, meaning it does not exhibit a significant electric dipole. In other words, the charges in a nonpolar molecule are balanced, and there are no ends with partial positive or negative charges.

Question 3

How is the polarity of bonds within a molecule analyzed?

Answer 3

The polarity of bonds is assessed by evaluating the difference in electronegativity between the atoms forming the bond.

Polar Bond: If the difference is between 0.4 and 1.7.
Nonpolar Bond: If the difference is less than 0.4.

Question 4

What is the relationship between molecular structure symmetry and Polarity?

Answer 4

The overall polarity of the molecule is influenced not only by the polarity of the bonds but also by the molecular geometry.

Question 5

What is the dipole moment?

Answer 5

When the atoms of a molecule share their electrons unevenly or distribute them asymmetrically among the atoms forming covalent bonds, they create what is called a dipole moment. This phenomenon occurs when one atom is more electronegative than another, causing that atom to attract the shared electron pair more strongly