Civil Engineering MCQAE Level Civil Engineering
In a BOD test, 300 mL of diluted sample is made up to 300 mL. Initial DO is 7.8 mg/L and final DO after 5 days is 3.6 mg/L. The BOD is
Environmental EngineeringGeneralMEDIUM
Choose the correct answer
A
2.1 mg/L
B
4.2 mg/L
C
None of these 3
D
8.4 mg/L
Correct Answer
B. 4.2 mg/L
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BOD = DO depletion x dilution factor = (7.8-3.6) x 300/300 = 4.2 mg/L.
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