REHS Practice Test Questions With Complete Solutions

Soil permeability procedure involves evaluating a soil core or test pit. What does the procedure yield? a. Permeability estimated seepage rate b. Permeability estimated application rate c. Permeability estimated range correct answer: b. Permeability estimate How does chlorine kill microorganisms and bacteria? a. By weakening enzymes and destroying internal organelles b. By attacking lipids in cell walls and destroying enzymes and structures inside c. By breaking bonds and poisoning the cell correct answer: b. By attacking lipids in cell walls and destroying enzymes and structures inside When chlorine is added to water, what is formed? a. Hypochlorous acid and hypochlorite ion b. Hypochlorite acid and hypochlorite ion c. Hypochloric acid and hypochlorite ion correct answer: a. Hypochlorous acid and hypochlorite ion What two acids are formed when you add liquefied chlorine gas (Cl2) to water? a. Hypochlorite acid and hydrochloric acid b. Hypochlorous acid and hydrochloric acid c. Hypochloric acid and hydrochloric acid correct answer: b. Hypochlorous acid (HOCL) and hydrochloric acid (HCl) What cause pH to jump? a. Low alkalinity, precipitation, algae growth b. High alkalinity, precipitation, algae growth c. Low alkalinity, high calcium hardness, algae growth correct answer: a. Low alkalinity, precipitation, algae growth What do you add to lower pH? a. Sodium bisulphate (NaHSO4) b. HCl c. aerate with CO2 d. all of the above correct answer: d. all of the above What do you add to raise pH? a. Sodium carbonate (Na2CO3) (Soda Ash) b. Sodium bicarbonate c. Sodium bisulphate correct answer: a. Sodium carbonate (Na2CO3) (Soda Ash) Why do you use algaecides in pool even though chlorine is used? a. Chlorine is not effective against algae b. Chlorine levels required to kill aglae are dangerously high c. Insurance against sloppy chlorination correct answer: c. Insurance against sloppy chlorination Ozone (O3) is ______ faster than chlorine: a. 1500X b. 2000X