Pure Substances and Mixtures — CHEMISTRY STD 6 — Question

A mixture consists of molecules of two or more substances (elements, compounds or both) in any proportion such that they do not undergo chemical change. For example, air is a mixture of a number of gases such as oxygen, nitrogen and carbon dioxide.Characteristics of mixtures :

1. The constituents in a mixture may be present in any ratio or proportion.
2. A mixture does not have any specific property of its own. In a mixture, each constituent exhibits its original properties.
3. A mixture does not have a fixed melting or boiling point.
4. The constituents of a mixture can be separated by simple physical means.