An unseeded BOD test is run using 25 ml of waste water mixed with 200 ml of pure water. The value of k at 20℃ is 0.22 day-1. The initial DO of the mixture is 12 mg/l. After 5 days the DO remains fixed at 4 mg/l. The remaining oxygen demand of the waste after 5 days isans.68.2 mg/lit35.9 mg/lt.29.3 mg/lit.14.6 mg/lit.

The BOD5 of a waste water is determined to be 240 mg/l at 20℃. The k value at 20℃ is known to be 0.23 day-1 . Calculate the BOD7 if the test were run at 10℃.ans.196.89 mg/l224.05 mg/l240 mg/l258.12 mg/l Previous Marked for Review Next

A wastewater sample with an initial dissolved oxygen (DO) concentration of 8 mg/L is incubated in a BOD bottle at 20°C for 5 days. After incubation, the DO concentration decreases to 3 mg/L. Calculate the BOD₅ of the wastewater sample.a.50 mg/Lb.250 mg/Lc.5 mg/Ld.25 mg/L◄ Previous page

Determine the BOD5 for a 10 mL sample, collected from wastewater stream in Jamdoli that is diluted to a total volume of 300 mL when the initial dissolved oxygen is 8.5 mg/L and after 5 days, has been reduced to 2.5 mg/L.