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. The procedure of evaporation under controlled temperature of a measured volume of water that has been filtered to remove all suspended solids, and calculating the weight of the residue to give results in parts per million (ppm) is used to determine:
a) total solids
b) total suspended solids
c) total dissolved solids
d) all of the above
2. The weight of residue from a measured volume of an unfiltered water sample is comprised entirely of:
a) dissolved solids
b) suspended solids
c) total solids
3. Total dissolved solids is a measure of:
a) the soluble constituents in water
b) the total sum of all cations and anions measured as respective ions
c) the total sum of either cations or anions, expressed in equivalent ppm of CaCO3
d) dissolved solids
e) all of the above
4. Water hardness means such water is hard to wash with and will form hard scale in pipes and boilers.
5. Cations of iron, barium and strontium contribute to water hardness.
6. When the hardness has been removed from the water and replaced with sodium or potassium, the water is called easy water because the adverse soap reactions have been eliminated and the water is now easy to wash with.
7. Strong acids generally come from organic sources, such as citric acid.
8. Free mineral acids (FMA) equal total mineral anions (TMA), when expressed in parts per million (ppm) as calcium carbonate (CaCO3), in water coming from a strongly acidic cation resin in the hydrogen form and with no sodium leakage.
9. Most natural waters contain carbonate and hydroxide alkalinity.
10. Water with 0.0000001 (or 1 X 10-7) grams of hydrogen ion in each liter of water would read __________ on the pH scale.