1. If a water has a 5.6 ppm chlorine demand and a one milligram per liter chlorine residual is desired, the chlorine feed dosage must be:

a. 1 ppm

b. 4.6 ppm

c. 5.6 ppm

d. 6.6 ppm


2. The correct number of coliform per 100 milliliters when a membrane filter count shows five coliform colonies and one milliliter of sample was filtered is:

a. not detectable

b. five

c. 500

d. too numerous to count


3. A 0.45 micron pore-diameter filter can be used to capture coliform bacteria. (True or False)


4. Photosynthesis is the process of producing man-made photographs. (True or False)


5. You can determine the chlorine residual in water by using this reagent:

a. diethyl-p-phenylenediamine (DPD)

b. ethylene dibromide (EDB)

c. sodium 2-(parasulfophenylazo)-1, 8-dihydroxy-3, 6-naphthalene disulfonate (SPADNS)

d. ethylenediaminetetraacetic acid (EDTA)


6. Algae contain chlorophyll. (True or False)


7. Sodium thiosulfate crystals are placed in laboratory bottles intended for collection of bacteriological samples to:

a. preserve the sample

b. feed the microorganisms until they can be analyzed in the laboratory

c. buffer pH fluctuation tendencies

d. neutralize any chlorine residual present in the sample


8. In the multiple-tube fermentation/most probable number (MPN) bacteriological analysis technique, the presumptive test for coliform is positive if upon incubation with a suitable agar medium:

a. gas is produced within 48 hours

b. visible bacterial colonies that exhibit a green metallic sheen are produced

c. the tubes exhibit a yellow or green color under white light

d. no gas is produced


9. Bacteria and blue-green algae are called prokaryotes because their cells lack distinct nuclei. (True or False)


10. ONPG and MUG refer to reagents used in testing for:

a. total heterotrophic bacteria counts

b. coliform bacteria

c. viruses

d. Giardia lamblia cysts