Chapter 9, Problem 9.41P

(a)

Interpretation Introduction

Interpretation:

The relative strength of carbon-oxygen double bond and carbon-oxygen single bond in formic acid is to be ranked.

Concept introduction:

A covalent bond is formed by the interaction of two nonmetals. Covalent compounds are formed by the sharing of electrons between two or more atoms. A covalent bond is the strong forces of attraction between the shared pairs of electrons and the nuclei of the combining atoms.

In the covalent bond, bond energy is the energy needed to overcome the attractive forces between the nuclei of atoms and the shared pair of electrons. Bond energy is the enthalpy change associated with breaking of bond of $1\text{mol}$ of gaseous molecule. The enthalpy associated with equation (1) is $\Delta H_{\text{bond}\text{breaking}}$ or ${\text{BE}}_{\text{AB}}$.

$\text{AB}\left(g\right)\to \text{A}\left(g\right)+\text{B}\left(g\right)$ (1)

The bond energy of a bond is directly related to the bond strength of a bond. Greater the bond strength of the bond more will be the bond energy of the bond and vice-versa.

Bond order is the number of electron pairs that are shared between the pair of atoms. The bond order of a pair of an atom is directly proportional to the strength of the bonds.

(b)

Interpretation Introduction

Interpretation:

The relative strength of the carbon-hydrogen bond and oxygen-hydrogen bond in formic acid is to be ranked.

Concept introduction:

A covalent bond is formed by the interaction of two nonmetals. Covalent compounds are formed by the sharing of electrons between two or more atoms. A covalent bond is the strong forces of attraction between the shared pairs of electrons and the nuclei of the combining atoms.

In the covalent bond, bond energy is the energy needed to overcome the attractive forces between the nuclei of atoms and the shared pair of electrons. Bond energy is the enthalpy change associated with breaking of bond of $1\text{mol}$ of gaseous molecule. The enthalpy associated with equation (1) is $\Delta H_{\text{bond}\text{breaking}}$ or ${\text{BE}}_{\text{AB}}$.

$\text{AB}\left(g\right)\to \text{A}\left(g\right)+\text{B}\left(g\right)$ (1)

The bond energy of a bond is directly related to the bond strength of a bond. Greater the bond strength of the bond more will be the bond energy of the bond and vice-versa. In the covalent bond, the strength of the bond is inversely related to the size of the atom.