CBSE Class 9 Answered
Vapour |
Gas |
A substance which under ordinary conditions is a solid or a liquid but under specific conditions is gaseous is called vapour. |
When a substance exists in the gaseous state under ordinary conditions that is, at room temperature and one atmospheric pressure, it is called a gas. |
A vapour is a substance which has experienced a phase change. |
A gas is a substance which has not, and will not experience a phase change. |
Vapour is a solid or a liquid at room temperature, that its natural state of matter is either a solid or a liquid. |
The natural state of matter for a gas is a gas. |
A vapour is a substance above its boiling point temperature. |
A gas is a substance above its critical temperature. |
Example: Iodine is a solid under ordinary conditions, but when it is heated, it changes into its gaseous state in the form of iodine vapours. |
Example: Oxygen, Nitrogen, Chlorine. |