Question

Cloud is a colloidal suspension of water droplets in air. Is it true or false?

Answer 1

Colloidal suspension basically refers to a solution where the size of solute particles is considered to be intermediate between that of the true solution and suspension. For example: milk, mayonnaise, butter, muddy water, gelatin, etc.

Complete solution:
The ice or water which forms clouds travels into the sky within the air in the form of water vapour. Water vapour gets occupied in the air mainly through evaporation (i.e. some of the water from lakes, ocean, and rivers changes into water vapour and travels in air. When air rises in the atmosphere it becomes cooler and is under the impact of less pressure. The cool air is actually saturated i.e. it cannot hold all water vapour so it condenses to form either small water droplets (liquid) or ice crystals (solid) and thus, leads to the formation of a cloud.
Hence, we can say that the cloud is a colloidal suspension of water droplets in air. Thus, the given statement is true.

Note: There are four types of colloids including sol (solid particles in a liquid), emulsion (between the two liquids), foam (gas particles in either a liquid or a solid), and aerosol (liquid or the solid particles in a gas). Thus, it means that clouds can fall under the category of aerosol colloids including a suspension of water droplets (i.e. water vapour) or small particulate matter (i.e. ice crystals) in a gas.