A) 4ppm
B) \[0.4,mg\,{{L}^{-1}}\]
C) 40ppm
D) \[20\,\text{mg}\,{{\text{L}}^{-1}}\]
Correct Answer: C
Solution :
Water pollution is measured by BOD (biochemical oxygen demand) and BOD is a standardised measurement of the amount of oxygen required by microorganism to cause the decomposition of organic matter over a period of 5 days at \[\text{20}{{\,}^{\text{o}}}\text{C}\text{.}\] \[\text{BOD }\,\text{=}\frac{\text{weight}\,\text{of oxygen(in mg)}}{\text{volume of water sample (in L)}}\] Given, Weight of oxygen = 0.2 g = 200 mg Volume of solution = 5 L \[BOD=\frac{200}{5}mg/L\] \[=40\,mg/L=40\,ppm\]You need to login to perform this action.
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