Chapter 8.4, Problem 31LC

Interpretation Introduction

Interpretation: The role of electronegativity values in determining the charge distribution in a polar covalent bond needs to be explained.

Concept Introduction: When two or more atoms interact with each other, a chemical bond can form between them. There are two types of bonds; ionic and covalent depending on the type of atoms involved in bonding. If there is a huge electronegativity difference between two atoms, an ionic bond is formed between them and if two atoms have comparable electronegativity values, a covalent bond is formed.

Explanation of Solution

Covalent bonds are formed by sharing of electrons between two atoms. Here, both atoms have comparable electronegativity values. Thus, instead of complete transfer, atoms share electron/s to form a bond. There are three types of covalent bonds depending on the relative electronegativity of bonded atoms. If atoms bonded together have nearly equal electronegativity, the bond formed by sharing of electrons between them is known as a non-polar covalent bond.

Similarly, if bonded atoms have unequal electronegativity, the atom with more electronegativity value will have a partial negative charge, and the atom with less electronegativity value will have a partial positive charge. The bond formed after sharing of electron/s between them will be polar in nature.

Thus, the charge distribution in a polar covalent bond takes place in such a way that an atom with a more electronegativity value will have a partial negative charge, and an atom with a less electronegativity value will have a partial positive charge.