Question

1. ________ is the process designed to kill or inactivate most microorganisms in water, including essentially all pathogenic (disease-causing) bacteria.

a. sterilization
b. uv treatment
c. application of chlorine
d. disinfection

1. which of the diseases listed is not caused by a waterborne pathogenic organism?

a. gastrointestinal anthrax
b. shigellosis
c. polio
d. all of these are water borne diseases

1. hypochlorous acid and hypochlorite when considered together are also known as the ________.

a. chlorine dose
b. chlorine demand
c. free chlorine

Explanation:

1. Disinfection targets most pathogens (including disease-causing bacteria) in water, while sterilization kills all microorganisms, UV treatment and chlorine application are specific disinfection methods, not the defined process itself.
2. Gastrointestinal anthrax is typically caused by ingesting contaminated meat, not waterborne pathogens. Shigellosis and polio are confirmed waterborne diseases.
3. Free chlorine refers to the combined active forms of hypochlorous acid (HOCl) and hypochlorite (OCl⁻) in water, which are the active disinfecting components of chlorine treatment.

Answer:

1. d. Disinfection
2. a. Gastrointestinal anthrax
3. c. free chlorine