Chapter 14, Problem 59A

(a)

Interpretation Introduction

Interpretation: The types of intermolecular forces acting in the liquid state of a given substance are to be discussed.

Concept introduction: Intermolecular forces in the case of nonpolar molecules were discussed by Van der Waal. So, these are also called Van der Waal forces.

Answer to Problem 59A

Forces will be dispersion forces.

Explanation of Solution

London dispersion forces are the weakest intermolecular forces present between the non-polar molecules. Due to the non-polar nature of argon, it exhibits London forces.

(b)

Interpretation Introduction

Interpretation: The types of intermolecular forces acting in the liquid state of a given substance are to be discussed.

Concept introduction: Intermolecular forces in the case of nonpolar molecules were discussed by Van der Waal. So, these are also called Van der Waal forces.

Answer to Problem 59A

In the case of $H_{2}O$ , there is an H-bonding present between the molecules.

Explanation of Solution

  $H_{2}O$ is a polar molecule. It involves hydrogen bonding between the molecules because of the small size and high electronegativity of oxygen and the availability of hydrogen in the molecule.

(c)

Interpretation Introduction

Interpretation: The types of intermolecular forces acting in the liquid state of a given substance are to be discussed.

Concept introduction: Intermolecular forces in the case of nonpolar molecules were discussed by Van der Waal. So, these are also called Van der Waal forces.

Answer to Problem 59A

SeO₂ is non-polar; hence forces will be dispersion forces.

Explanation of Solution

London dispersion forces are the weakest intermolecular forces present between the non-polar molecules. This is because in $Se{O}_2$ , dipole moments cancel each other due to linear geometry and hence the molecule is non-polar and exhibit Van der Waal forces.

(d)

Interpretation Introduction

Interpretation: The types of intermolecular forces acting in the liquid state of a given substance are to be discussed.

Concept introduction: Intermolecular forces in the case of nonpolar molecules were discussed by Van der Waal. So, these are also called Van der Waal forces.

Answer to Problem 59A

BF₃ molecules exhibit London dispersion forces.

Explanation of Solution

BF₃ is a trigonal planar. All the dipole moments cancel resulting in zero dipole moment and hence a non-polar molecule. So, the forces present between them is London dispersion forces.