Question

Which gas is used to disinfect water?

• A. Nitrogen
• B. Hydrogen
• C. Chlorine
• D. Carbondioxide

Hint:

Chlorine is the most common water disinfectant because it: (1) kills pathogens effectively, (2) provides residual protection, (3) is economical. Swimming pools also use chlorine to maintain hygiene.

Answer 1

The Correct Option is C

To determine which gas is used to disinfect water, we need to evaluate the given options based on their common uses and properties:

1. Nitrogen: Nitrogen is an inert gas, often used in the food industry to preserve freshness, but it is not used for water disinfection.
2. Hydrogen: Hydrogen is highly flammable and not used for disinfecting purposes.
3. Chlorine: Chlorine is widely known for its disinfecting properties. It is commonly used in water treatment processes to kill bacteria and other pathogens, making water safe for human consumption.
4. Carbon dioxide: Carbon dioxide is primarily used for carbonation in beverages and does not have disinfecting properties.

Based on the above analysis, Chlorine is the gas used to disinfect water. Chlorine is effective at eliminating harmful microorganisms, thus ensuring the safety of drinking water.

This practice is ubiquitous in municipal water treatment facilities across the globe. The chemical reactions involved in water disinfection by chlorine are well-documented, where chlorine interacts with water to form hypochlorous acid (HOCl), a potent disinfectant.