What is one method used to neutralize acidic water?

The method of adding lime to neutralize acidic water is based on the chemical reaction that occurs when calcium hydroxide (lime) interacts with acids present in the water. When lime is added, it increases the pH level by reacting with hydrogen ions, which are responsible for acidity. This reaction can effectively raise the pH of the water, making it less acidic and bringing it closer to a neutral level. This process is often utilized in water treatment facilities to ensure that the water meets regulatory standards and is safe for consumption and environmental discharge.

In contrast, other methods listed do not directly address the need for neutralizing acidity in water. For instance, adding sulfur is more commonly associated with the treatment of alkaline waters or can lead to other forms of pollution if not handled properly. Salt does not neutralize acid; rather, it might increase the concentration of dissolved ions in the water without adjusting pH levels. Similarly, activated carbon is primarily used for odor removal, taste improvement, and the adsorption of organic compounds, rather than for directly altering the pH of water.