Q. 8.1 - An Introduction to General, Organic, and Biological Chemistry

Question

Use the kinetic molecular theory of gases to explain each of the following:

a. Gases move faster at higher temperatures.

b. Gases can be compressed much more easily than liquids or solids.

c. Gases have low densities.

Step-by-Step Solution

Answer

Kinetic molecular theory used in following statements is:

(a) The typical kinetic energy of gas molecules is linearly proportional to kelvin temperature.
(b) Actual volume occupied by gas molecules is negligible compared to volume that gas occupies.
(c) Gas molecules have less force of attraction and occupies entire space of container within which they are kept.

Part (a) Step 1: Given Information

We are given statement: Gases move faster at higher temperatures, 

We need to explain statement using kinetic molecular theory of gases.

Part (a) Step 2: Explanation

According to molecular kinetic theory, the average kinetic energy of gas molecules is linearly proportional to kelvin temperature. The kinetic energy of the molecule increases as the temperature rises. As a result, it has been established that gases travel more quickly at higher temperatures.

Part (b) Step 1: Given Information

We are given statement: Gases can be compressed much more easily than liquids or solids.

We need to explain statement using kinetic molecular theory of gases.

Part (b) Step 2: Explanation

The real volume occupied by gas molecules is exceedingly little in comparison to the volume that gas occupies, according to kinetic molecular theory. As a result, compressing gases is easier than compressing liquids or solids.

Part (c) Step 1: Given Information

We are given statement: Gases have low densities.

We need to explain statement using kinetic molecular theory of gases.

Part (c) Step 2: Explanation

Gas molecules, according to the kinetic theory of gases, have a lower attraction force. They take up the entire room where they are housed. Smaller gas masses have more volume, resulting in a lower density.