Which of the following statements is CORRECT?A. No oxygen consumption in biological oxygen demand (BOD) test indicates the existenceof organic compounds in water sample.B. Secondary treatment involves the use of chemical disinfectants.C. Biomagnification is also known as bioaccumulation.D. Sediments could be classified as dissolved solids.E. Human and animal wastes are examples of oxygen-consuming wastes

Water would become polluted due to biodegradable waste content in it. During the decomposition of the waste, the oxygen naturally dissolved in water would be:Question 14Select one:A.All of the optionsB.Used up by the decomposing wasteC.In high demand in the BOD- Oxygen Biological DemandD.starved to the aquatic lifeE.Depleted

The quantity of oxygen that is essential for microorganisms to break down the biological substance existing in a specific capacity of a sample water is called ______________.Select one:a.Marine Necessityb.Thermal demand of oxygenc.Chemical oxygen demandd.Biochemical oxygen demand

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.35.9 mg/lt.14.6 mg/lit.29.3 mg/lit.68.2 mg/lit

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

Primary and secondary treatment of wastewater leads to _______.a.High BODb.Increase in DOc.Low BOD and CODd.High COD