Q.6.146 - An Introduction to General, Organic, and Biological Chemistry

Question

Indicate the major type of intermolecular forces-(1)ionic bonds, (2) dipole-dipole attractions, (3) hydrogen bonds, (4) dispersion forces- that occur. between particles of the following. 

a.${\mathrm{CHCl}}_3$${\mathrm{CHCl}}_3$

b. ${\mathrm{H}}_2\mathrm{O}$

c. $\mathrm{LiCl}$

d. ${\mathrm{OBr}}_2$${\mathrm{OBr}}_2$

e. $\mathrm{HBr}$$\mathrm{HBr}$

f. $\mathrm{IBr}$

Step-by-Step Solution

Answer

a. (2) dipole-dipole attractions

b. (3) hydrogen bonds

c. (1) ionic bonds

d. (2) dipole-dipole attractions

e. (2) dipole-dipole attractions 

f. (4) dispersion forces

Step 1: Part (a) Given Information

To determine the intermolecular forces present in the molecule.

Step 2: Part (a) Explanation

• ${\mathrm{CHCl}}_3$ is a polar molecule, thus it has dipole-dipole interactions.
• It also has dispersion forces.

• The intermolecular forces present in this molecule are dipole-dipole interactions due to the result of dipoles in a molecule (a result of attraction between a positive and a negative end).

Step 1: Part (b) Given Information

To determine the intermolecular forces present in the molecule.

Step 2: Part (b) Explanation

• Water has strong hydrogen bonding as it is composed of hydrogen and oxygen atoms.
• The electronegativity difference between these two atoms results in a polar nature of this compound.

Step 1: Part (c) Given information

To determine the intermolecular forces present in the molecule.

Step 2: Part (c) Explanation

• Lithium chloride is an ionic compound, it is composed of lithium and chloride ions.
• The ions are strongly held together by ionic forces or bonds i.e., the type of bond formed between two oppositely charged species.

Step 1: Part (d) Given Information

To determine the intermolecular forces present in the molecule.

Step 2: Part (d) Explanation

• The intermolecular forces present in ${\mathrm{OBr}}_2$ are Dipole-dipole attractions.
• Oxygen dibromide is a polar molecule, that results in a dipole moment due to which the molecule has dipole-dipole interactions.

Step 1: Part (e) Given Information

To determine the intermolecular forces present in the molecule.

Step 1: Part (e) Explanation

• Hydrogen bromide is a polar molecule.
• This molecule exhibits dipole-dipole interactions, due to the large electronegativity difference between hydrogen and bromine atoms.

Step 1: Part (f) Given information

To determine the intermolecular forces present in the molecule.

Step 2: Part (f) Explanation

• In the iodine bromide molecule, there are weak London dispersion forces.
• The dipole moment between the iodine and bromine atom is very weak in $\mathrm{IBr}$ molecule.