Certification Action Line features questions and answers typical of those appearing in Water Quality Association (WQA) certification examinations. Some answers may not satisfy everyone of every condition.


1. Water hardness is made up of:
a) calcium
b) magnesium
c) multivalent cations
d) a and b
e) all of the above

2. Water hardness cations attract and bind up with:
a) natural skin oils
b) phosphate ions
c) detergents
d) all of the above

3. Water hardness is a concern for reverse osmosis systems because of its potential for:
a) oxidation
b) hydrolysis
c) precipitation
d) all of the above

4. A substance likely to appear first as a contaminant in high purity water systems is:
a) water hardness
b) sodium
c) iron
d) aluminum

5. Anions that remove hydrogen from solution are known as:
a) alkalinity
b) sulfates
c) nitrates
d) chlorides
e) all of the above

6. Most all of the alkalinity in naturally occurring water is in the form of:
a) bicarbonate
b) carbonate
c) hydroxide

7. Sulfate solubility can be controlled by controlling the _________ in water.
a) chlorides
b) sodium and potassium
c) divalent cations
d) suspended solids

8. The problem with chlorides in water is:
a) scale formation
b) corrosion
c) laxative effect

9. Cations, such as iron, manganese, copper and zinc, can catalyze more rapid oxidation in ion exchange resin crosslinking and in reverse osmosis membranes.
a) True
b) False

10. Aluminum in water is a:
a) dispersant of organic colloids
b) more soluble when silica is present
c) most soluble over the pH range of 6 to 8
d) concern in the dialysis industry
e) all of the above