Reference no: EM13772768
1. Which of the following statements are true concerning the Safe Drinking Water Act secondary standards?
a. They are enforceable.
b. They are for compounds which make drinking water aesthetically pleasing to consumers.
c. They enable drinking water to be potable.
d. They enable drinking water to be palatable.
e. All of the above.
2. A pollutant which degrades according to the equation dC/dt = -kC is said to react according to?
a. Zero order kinetics.
b. First order kinetics.
c. Second order kinetics.
d. None of above.
e. All of the above.
3. Recarbonation is necessary in drinking water treatment because:
a. The chemicals added during water treatment reduce the pH.
b. The chemicals added during water treatment increase the pH.
c. The chemicals added during water treatment consume carbon dioxide.
d. All of the above
e. None of the above
4. If the current mineral reserve of iron is 65,400 Tg, the annual demand is 1060 Tg and we assume the demand increases 1.2% annually, how long will the reserve last?]
a. 62 years
b. 73 years
c. 55 years
d. 46 years
e. None of the above
5. A solution that has a [OH-] concentration of 10-3 M has a pH of]
a. 11
b. 7
c. 3]
d. 10
e. -3
f. 12
Name: _______________________________________
6. A dual media rapid sand filter used what two types of porous media for screening of small-sized particulate matter]
a. Anthracite coal
b. Garnet]]
c. Gravel]
d. Sand]
e. Clay]
7. The unit process that is used primarily for the removal of settleable solids such as coffee grinds and sand is:
a. Comminutor
b. Primary settling tank
c. Grit chamber
d. Secondary clarifier
e. Bar screen]
8. The hardness of water is most commonly due to the presence of
a. CO32-
b. HCO3-
c. Ca2+
d. Mg2+
e. Clf.
All of above]
g. None of the above
9. The single-most important purpose of secondary treatment is
a. Removal of suspended solids
b. Removal of suspended BOD
c. Removal of soluble BOD
d. Denitrification
e. Nitrification
f. All of above
10. The purpose of disinfection in drinking water treatment is/are concentration of 10-
a. Kill pathogens
b. Keep residual chlorine to the end point of the consumer
c. More palatable water
d. Prevent disinfection by-products
e. Reduce the turbidity