Problem 19 - A Complete Resource Book in Chemistry for JEE Main

Question

Water is often treated with chlorine to (a) kill germs (b) remove hardness (c) increase oxygen content (d) remove suspended particles

Step-by-Step Solution

Answer

Chlorine is used to kill germs in water.

Step 1: Identifying the Function of Chlorine

Chlorine is commonly used in water treatment processes. It's crucial to understand that chlorine's primary role is to act as a disinfectant. Its main function is to neutralize microorganisms in the water, ensuring it is safe for consumption.

Step 2: Evaluating the Options

Review each option provided: (a) kill germs, (b) remove hardness, (c) increase oxygen content, (d) remove suspended particles. Chlorine is used specifically to kill germs. Options b, c, and d relate to functions that chlorine does not typically perform.

Step 3: Matching Chlorine's Function to the Correct Option

Since chlorine is used to disinfect and kill germs, we find that option (a) appropriately describes the role of chlorine. Chlorine is not added to remove hardness, increase oxygen content, or remove suspended particles.

Key Concepts

Water Disinfection

Water disinfection is a critical process in ensuring that water is free from pathogens that can cause diseases. Chlorine plays a pivotal role in this process. When added to water, chlorine acts as a disinfectant. This means it helps eliminate harmful microorganisms present in the water. These microorganisms can include bacteria, viruses, and protozoa, all of which can pose serious health risks if consumed.

• Chlorine is inexpensive and highly effective at low concentrations, making it an ideal choice for widespread water treatment.
• Due to its effectiveness, chlorine is widely used in municipal water systems to purify water before it reaches consumers.

Chlorine helps ensure the water you drink and use is safe and free from disease-causing organisms. Its role in water treatment cannot be overstated, as it stands as a frontline defense against waterborne illnesses.

Microorganism Neutralization

Neutralization of microorganisms is essential to making water safe. When chlorine is introduced to water, it reacts with water molecules to form hypochlorous acid and hypochlorite ions. These compounds are highly effective at penetrating the cell walls of microorganisms.
Once inside the microorganism, these compounds cause reactions that destroy organic matter within the cell. By disrupting the vital processes of these cells, chlorine effectively kills microorganisms, rendering them harmless. This process of killing and inactivating germs ensures that the water becomes safer for human consumption.

• Hypochlorous acid, one of the products formed, is particularly effective because it is neutral in charge, allowing it to easily penetrate cell walls.
• This method of microorganism neutralization ensures a high level of water safety and hygiene.

Without such neutralization methods, our water supplies would remain vulnerable to contamination, resulting in potential health crises.

Water Safety

Water safety is a top priority in public health, and treating water with chlorine is key to achieving it. Safe water means it is free from pollutants and pathogens that can cause illnesses. Chlorine disinfection is a well-established method that helps ensure the safety of our drinking water.
By killing microorganisms, chlorine makes sure the water reaching homes, schools, and businesses is safe to use and drink. This helps prevent outbreaks of waterborne diseases such as cholera, typhoid, and dysentery.

• Continuous monitoring and controlling the amount of chlorine added is vital to ensure optimal water safety and quality.
• By maintaining chlorine levels within recommended limits, water treatment facilities can provide safe drinking water without any negative effects.

Thus, chlorine's role in maintaining water safety is indispensable, ensuring public health is protected and water sources remain uncontaminated.