Chapter 10, Problem 10.8VP

(a)

Interpretation Introduction

Interpretation: The questions related to Figure $\text{P10}\text{.8}$ are to be answered.

Concept introduction: Electrostatic potential map represents the distribution of charge in the molecule in three dimensions. It is used to find interactions between molecules.

The intermolecular forces are present in all the substance.

There are three types of intermolecular forces are present that is London forces, ion-dipole interactions and dipole-dipole interactions.

To determine: The predominant intermolecular forces in each of the given substances in the electrostatic potential maps.

Answer to Problem 10.8VP

Solution

Helium is represented by A; it has London forces as the predominant intermolecular forces.

Ethylene glycol is represented by B and ethanol is represented by G. Hydrogen bonds are the predominant intermolecular forces present in both molecules.

Ethane is represented by C, Carbon tetrachloride is represented by H and iodine is represented by I. London forces are present as the predominant intermolecular forces in these molecules.

Dimethyl ether is represented by E; it has dipole-dipole interactions as the predominant intermolecular forces present in the molecule.

Explanation of Solution

Explanation

The figure is given below.

Figure 1

In the above Figure, Helium is represented by A. It is a monatomic noble gas. In this molecule no chemical bonding is present. So, it has London forces are present as the predominant intermolecular forces.

In the above Figure, ethylene glycol is represented by B and ethanol is represented by G. They both have $\text{O}-\text{H}$ bonds. The $\text{O}-\text{H}$ bond has polar nature. So, hydrogen bonds are the predominant intermolecular forces present in both molecules.

In the above Figure, Ethane is represented by C, Carbon tetrachloride is represented by H and iodine is represented by I. All these are non polar molecules.

So, London forces are present as the predominant intermolecular forces in these molecules.

In the above Figure, Dimethyl ether is represented by E and it has $\text{C}-\text{O}$ bond which is polar in nature.

So, it has dipole-dipole interactions as the predominant intermolecular forces present in the molecule.

(b)

Interpretation Introduction

To determine: The substance requires the lowest temperature to condense.

Answer to Problem 10.8VP

Solution

Figure A represents helium and it requires the lowest temperature to condense.

Explanation of Solution

Explanation

The Figure for helium is represented by A is given below.

Figure A

The Figure A represents the helium molecule. In this molecule, there is a weak force of interactions because atoms are present far away from each other.

Due to weak intermolecular forces the energy required to break the molecules apart is also less. The lower temperature is required for condensation in this type of molecule.

So, helium has weakest intermolecular forces due to small size and requires lower temperature for condensation.

(c)

Interpretation Introduction

To determine: The representations which are isomer of one another.

Answer to Problem 10.8VP

Solution

Figure E and G are the isomers of one another.

Explanation of Solution

Explanation

Isomers are those molecules which have different geometrical arrangements with same chemical formula.

Figure E

Figure G

In the above Figure E represents dimethyl ether molecule and Figure G represents ethanol molecule.

They both have same chemical formula ${\text{C}}_{\text{2}}{\text{H}}_{\text{2}}{\text{O}}_{\text{6}}$. They have different geometrical arrangements.

So, they are isomers of one another.

(d)

Interpretation Introduction

To determine: The molecules which will dissolve in ethanol and in carbon tetrachloride out of ethylene glycol and iodine and the name of intermolecular force responsible for it.

Answer to Problem 10.8VP

Solution

Figure B that represents Ethanol glycol is dissolves in ethanol.

Figure I that represents iodine is dissolve in carbon tetrachloride.

Hydrogen bonding and London forces are the intermolecular forces responsible.

Explanation of Solution

Explanation

The Figures B and I, H and G are given below.

Figure 2

In the above Figure 2, B represents Ethanol glycol and I represents iodine molecule.

Polar solvent dissolve polar solute.

Ethanol glycol and ethanol are polar molecules. So, ethanol glycol is dissolve in ethanol which is represented by G in the above Figure.

Hydrogen bonding is the intermolecular forces that are present in both these molecules.

Iodine and carbon tetrachloride which is represented by H in the above Figure are non polar molecules.

Iodine is dissolve in carbon tetrachloride. London forces are present between these molecules.

(e)

Interpretation Introduction

To determine: The process that shows an increase in partial pressure.

Answer to Problem 10.8VP

Solution

The process which is shown in Figure D and F show increase in partial pressure.

Explanation of Solution

Explanation

Figure D and F is shown below.

Figure D

Figure F

In the above Figure D and F the molecules which are shown by the red color are increasing in number. The increase in the number of molecules results in the increase collisions with the walls of the container. Thus, partial pressure also increases.

So, the process D and F show increase in partial pressure.

(f)

Interpretation Introduction

To determine: The process that occurs due to an increase in temperature.

Answer to Problem 10.8VP

Solution

Figure D shows the process in which the partial pressure is increasing when the temperature is increased.

Explanation of Solution

Explanation

Figure D

In the above Figure D, the molecules which are shown by the red color are same in both initial and final condition.

When temperature is increasing, more molecules are going to gas phase in the Figure D.

So, Figure D shows the process in which the partial pressure is increasing.

Conclusion

1. a) The predominant intermolecular forces in each of the given substances have been rightfully stated.
2. b) Figure $\text{A}$ represents helium and it requires the lowest temperature to condense.
3. c) Figure E and G are the isomers of one another.
4. d)  Figure B that represents Ethanol glycol is dissolves in ethanol.

   Figure I that represents iodine is dissolve in carbon tetrachloride.

   Hydrogen bonding and London forces are the intermolecular forces responsible.

5. e) The process which is shown in Figure D and F show increase in partial pressure.
6. f) Figure D shows the process in which the partial pressure is increasing when the temperature is increased.