Top 250+ Solved Waste Water Treatment MCQ Questions Answer
Q. How much chromium is required to provide oxidation resistance for use over 1000oC?
a. 1%
b. 6%
c. 12%
d. 17%
Q. % chromium mixed with ______ can be used up to 1100oC.
a. Nickel
b. Chromium
c. Aluminum
d. Silicon
Q. Which of these metals does not require alloying for oxidation resistance?
a. Iron
b. Copper
c. Aluminum
d. Molybdenum
Q. Galvanized ion is made by dipping low carbon steel in molten zinc at ________
a. 100oC
b. 150oC
c. 200oC
d. 450oC
Q. Which of these is not a way to prevent intergranular corrosion?
a. Reduction of carbon level
b. Quenching
c. Addition of carbide forming elements
d. Reduction of alloying elements
Q. Dezincification of brass is prevented by addition of ________
a. Nickel
b. Zinc
c. Arsenic
d. Tungsten
Q. Season-cracking can be prevented by cold-working of brass at _________
a. 15oC
b. 100oC
c. 300oC
d. 550oC
Q. How can caustic embrittlement be avoided?
a. Addition of nickel
b. Increasing potential
c. Decreasing carbon
d. Adding tannins
Q. A grit chamber is usually installed ______ primary sedimentation tanks.
a. Before
b. After
c. In between
d. In
Q. Grit chambers are constructed to prevent their accumulation in _______
a. Sedimentation tank
b. Sludge digesters
c. Coagulation tank
d. Sand filter
Q. Grit chamber is similar to which of the following?
a. Screening unit
b. Sedimentation tank
c. Coagulation tank
d. Sand bed