Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
JEE Main202124 Feb 2021Evening ShiftChemistryEnvironmental ChemistryActual

Given below are two statements: Statement I: The value of the parameter "Biochemical Oxygen Demand (BOD)" is important for survival of aquatic life. Statement II: The optimum value of BOD is 6 . 5 ppm . In the light of the above statements, choose the most appropriate answer from the options given below:

Options

  1. AStatement I is true but Statement II is false
  2. BStatement I is false but Statement II is true
  3. CBoth Statement I and Statement II are false
  4. DBoth Statement I and Statement II are true

Correct answer

A. Statement I is true but Statement II is false

Step-by-step solution

Clean water would have BOD value of less than 5 ppm whereas highly polluted water could have a BOD value of 17   ppm or more. For survival of aquatic life dissolved oxygen is responsible its optimum limit 6 . 5   ppm and optimum limit of BOD ranges from 10 - 20   ppm & BOD stands for biochemical oxygen demand.

Practice Environmental Chemistry on Quantrex Academy →

More from Environmental Chemistry

The possibility of photochemical smog formation will be minimum at 2023Which of the following are the Green house gases? A. Water vapour B.Ozone C. I 2 D.Molecular hydrogen Choose the most appropriate answer from the options given below : 2023The radical which mainly causes ozone depletion in the presence of UV radiations is : 2023Match List I with List II List I List II A Nitrogen oxides in air I Eutrophication B Methane in air II pH of rain water becomes 5 . 6 C Carbon dioxide III Global warming D Phosphat 2023Which of the following compounds is an example of Freon? 2023Given below are two statements : Statement-I : If BOD is 4 ppm and dissolved oxygen is 8 ppm , then it is a good quality water. Statement-II : If the concentration of zinc and nitr 2023The delicate balance of CO 2 and O 2 is NOT disturbed by 2023Match List I with List II List I Industry List II Waste Generated (A) Steel plants (I) Gypsum (B) Thermal power plants (II) Fly ash (C) Fertilizer Industries (III) Slag (D) Paper m 2023 Full Environmental Chemistry list All JEE Main PYQs