A river sample has a very high biochemical oxygen demand (BOD). What does this show?

The water is very cleanCorrect answerYour answerThe water has too much dissolved oxygenCorrect answerYour answerThe water is too salty to drinkCorrect answerYour answerThe water holds a lot of organic pollutionCorrect answerYour answer

Show the answer and explanation

CorrectNot quiteAnswer D

Correct answer: D

BOD is the oxygen that microbes need to break down the organic matter in a water sample.
More sewage or organic waste means more oxygen demanded, so a high BOD means badly polluted water.

Concept: Biochemical oxygen demand
Typical timeTypical: 60 s
Your timeYours: —

The rule this testsAir, water, soil and noise pollution

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A river sample has a very high biochemical oxygen demand (BOD). What does this show?

Explanation