Question

A factory disposed its dilute acidic waste into the nearby river that killed fishes and plants. which substance must be added to this waste before disposal?

Answer 1

Factories as such produce acidic wastewater that require proper treatment before being disposed into river/lakes.

The wastewater can be treated by adding a substance called Lime. Lime is alkaline, so it can be used to adjust the pH of water containing metallic and acidic wastes. It neutralizes the acids and helps in removing metallic wastes by precipitating them into solids that are removable.