Factors not affecting bacterial efficiency of chlorine are

Explanation:

Factors Not Affecting Bacterial Efficiency of Chlorine

Chlorine is one of the most widely used disinfectants for water treatment due to its strong oxidizing properties and ability to inactivate a variety of microorganisms, including bacteria. However, the efficiency of chlorine as a disinfectant can be influenced by several factors. These include the water's chemical composition, physical characteristics, and the presence of various compounds. The question asks us to identify the factor that does not affect the bacterial efficiency of chlorine, and the correct answer is Option 2: Coagulants used.

Detailed Explanation:

The addition of coagulants during water treatment is a process primarily aimed at removing suspended particles, turbidity, and colloidal impurities from water. This process does not directly interact with chlorine or its ability to kill bacteria. Coagulation is a separate step in the water treatment process that precedes disinfection. The following reasons explain why the use of coagulants does not affect the bacterial efficiency of chlorine:

• Purpose of Coagulation: Coagulants such as alum (aluminum sulfate) or ferric chloride are used to aggregate fine particles into larger flocs, which can then be removed through sedimentation or filtration. This step is unrelated to the disinfection process where chlorine is applied.
• No Direct Interaction: Coagulants do not chemically react with chlorine to form compounds that would inhibit its disinfectant properties. Therefore, they do not interfere with chlorine's ability to inactivate bacteria.
• Separate Treatment Stages: The coagulation and disinfection stages in water treatment are independent of each other. Coagulation improves the physical quality of water, while disinfection ensures microbial safety.