Aeration of water is done to remove 

Explanation:

• Aeration involves exposing water to air, which helps remove dissolved gases like hydrogen sulfide responsible for bad odor.

• It also helps oxidize dissolved iron and manganese, improving taste and smell.

• Aeration does not remove hardness, bacteria, or colour directly.

• It is a common preliminary water treatment step to improve water quality and acceptability.

 Additional Information

• Coagulation and Flocculation: Chemicals (like alum) are added to water to cause small suspended particles to clump together into larger particles (flocs) which settle out, clarifying the water.

• Filtration: Water passes through filters (sand, gravel, charcoal) to remove remaining suspended solids, turbidity, and some microorganisms.

• Disinfection: Chemicals like chlorine, ozone, or UV light are used to kill or deactivate harmful pathogens, ensuring water is safe to drink.

• Softening: Removes hardness-causing minerals (calcium, magnesium) using processes like lime-soda treatment or ion exchange.

• Sedimentation: Allows heavy particles to settle at the bottom of tanks before filtration, reducing the load on filters.

• Activated Carbon Treatment: Removes organic compounds, odors, and some chemicals through adsorption on carbon surfaces.