Gases & Solutions
States of Matter
When a sample of a gas is compressed at constant temperature from to . Its volume changes from to
Which statements are possible explanations for this result?
1. The gas does not behave ideally
2. The gas partially liquefies
3. Some of the gas is lost from the container.
- 1, 2 and 3 are correct
- 1 and 2 only are correct
- 2 and 3 only are correct
- 1 only is correct
Correct Answer: Option(b)
As pressure increases, the volume of a gas becomes very small and approaches zero. While it does approach a small number, it will not be zero because molecules do occupy space (i.e. have volume) and cannot be compressed. (2) Intermolecular forces do exist in gases. These become increasingly important in low temperatures, when translational (definition of translational, please) molecular motion slows down, almost to a halt. However, at high temperatures, or even normal, every day temperatures, the intermolecular forces are very small and tend to be considered negligible.
gases can be liquefied by one of three general methods: 1) By compressing the gas at temperatures less than its critical temperature; In this approach, the application of pressure alone is sufficient to cause a gas to change to a liquid. For example, ammonia has a critical temperature of 271°F (133°C).