7. which of these ph readings indicates a base wastewater?\na. 3\nb. 5\nc. 6\nd. 10\n8. \schedule 40\ refers…
7. which of these ph readings indicates a base wastewater?\na. 3\nb. 5\nc. 6\nd. 10\n8. \schedule 40\ refers to pipe\na. flow capacity\nb. frication loss\nc. tubing strength\nd. wall thickness\n9. hydrogen peroxide controls odors by\na. decreasing the do\nb. neutralizing the ph\nc. oxidizing sulfide compounds\nd. providing a source of hydrogen ions\n10. the record log of a hydraulic cleaning operation should include\na. feet of rod used\nb. camera malfunction\nc. location of dropped joints\nd. type and amount of material removed from downstream manhole\n11. what should be considered when providing trench shoring?\na. cost - to - benefit ratio\nb. depth of trench\nc. pipe material\nd. grade of sewer\n12. biological activity in long, sluggish - flow, flat - grade sewer lines will likely\na. increase the carrying capacity of the line\nb. stop toxic gas production\nc. decrease line sediment\nd. create oxygen deficiency in the air in manholes, sewers, or wet wells\n13. a ph of 6.0 is\na. acid\nb. alkaline\nc. neutral\nd. basic
Answer
7.
Brief Explanations:
A pH value of 7 is neutral. Values less than 7 are acidic, and values greater than 7 are basic (alkaline). Among the options, 10 is greater than 7.
Answer:
d. 10
8.
Brief Explanations:
"Schedule 40" is a standard that refers to the strength of the tubing (pipe). It is related to the pressure - handling capacity which is a measure of strength.
Answer:
c. Tubing strength
9.
Brief Explanations:
Hydrogen peroxide ((H_2O_2)) can oxidize sulfide compounds ((S^{2 -})) which are often responsible for odors. For example, in the reaction (H_2O_2+S^{2 -}\to S + H_2O) (simplified form), it oxidizes the sulfide.
Answer:
c. Oxidizing sulfide compounds
10.
Brief Explanations:
The record log of a hydraulic cleaning operation should include relevant operational details. The type and amount of material removed from the downstream manhole is a key operational and performance - related detail.
Answer:
d. Type and amount of material removed from downstream manhole
11.
Brief Explanations:
When providing trench shoring, the depth of the trench is a crucial factor. Deeper trenches require more robust shoring to prevent collapse.
Answer:
b. Depth of trench
12.
Brief Explanations:
In long, sluggish - flow, flat - grade sewer lines, biological activity (such as microbial respiration) can consume oxygen. Microorganisms use oxygen for their metabolic processes, leading to an oxygen deficiency in the air in manholes, sewers, or wet wells.
Answer:
d. Create oxygen deficiency in the air in manholes, sewers, or wet wells
13.
Brief Explanations:
A pH of 7 is neutral. A pH less than 7 (such as 6.0) is acidic.
Answer:
a. Acid