The water quality of a pond was analysed and its BOD was found to be \( 4 \). The pond has :
Very clean water
Slightly polluted water
Highly polluted water
Water has high amount of fluoride compounds
BOD values (in ppm) for clean water \( (A) \) and polluted water \( (B) \) are expected respectively as:
Match List I and List IIChoose the correct answer from the options given below:
How can photochemical smog be controlled?
The delicate balance of \( \mathrm{CO_2} \) and \( \mathrm{O_2} \) is NOT disturbed by:
Match List I with List II.
Choose the correct answer from the options given below:
Match List-I with List-II.
Which of these reaction is not a part of breakdown of ozone in stratosphere?
Which of the following is true about freons?
Correct statement about smog is:
The green house gas/es is (are): (A) Carbon dioxide (B) Oxygen (C) Water vapour (D) Methane Choose the most appropriate answer from the options given below:
The group of chemicals used as pesticide is:
A. Ammonium salts produce haze in atmosphere.B. Ozone gets produced when atmospheric oxygen reacts with chlorine radicals.C. Polychlorinated biphenyls act as cleansing solvents.D. ‘Blue baby’ syndrome occurs due to the presence of excess of sulphate ions in water.Choose the correct answer from the options given below:
Some gases are responsible for heating of atmosphere (green house effect). Identify from the following the gaseous species which does not cause it.
Correct statement about photo-chemical smog is:
Identify X, Y and Z in the following reaction. (Equation not balanced):
$ \text{CIO}_{} + \text{NO}_2 \rightarrow \underline{\text{X}} \xrightarrow{\text{H}_2\text{O}} \underline{\text{Y}} + \underline{\text{Z}} $
Which of the following are the Green house gases ?A. Water vapourB. OzoneC. \( \mathrm{I_2} \)D. Molecular hydrogenChoose the most appropriate answer from the options given below :
Match List I with List II
In stratosphere most of the ozone formation is assisted by :
Which among the following pairs has only herbicides?
The eutrophication of water body results in :
Formation of photochemical smog involves the following reaction in which A, B and C are respectively.\( (i)\; \mathrm{NO_2} \xrightarrow{h\nu} A + B \) \( (ii)\; B + \mathrm{O_2} \longrightarrow C \) \( (iii)\; A + C \longrightarrow \mathrm{NO_2} + \mathrm{O_2} \) Choose the correct answer from the options given below:
The gas 'A' is having very low reactivity reaches to stratosphere. It is non-toxic and non-flammable but dissociated by UV-radiations in stratosphere. The intermediates formed initially from the gas 'A' are:
Water sample is called cleanest on the basis of which one of the BOD value given below.
Reducing smog is a mixture of :
The possibility of photochemical smog formation is more at.
Match List I with List II:
Given below are two statements:Statement I: The non bio-degradable fly ash and slag from steel industry can be used by cement industry.Statement II: The fuel obtained from plastic waste is lead free.In the light of the above statements, choose the most appropriate answer from the options given below:
Sulphur dioxide is one of the components of polluted air. \( \mathrm{SO_2} \) is also a major contributor to acid rain. The correct and complete reaction to represent acid rain caused by \( \mathrm{SO_2} \) is:
Given below are two statements:Statement I: In polluted water values of both dissolved oxygen and BOD are very low.Statement II : Eutrophication results in decrease in the amount of dissolved oxygen. In the light of the above statements, choose the most appropriate answer from the options given below:
Given below are two statements: one is labeled as Assertion A and the other is labeled as Reason R.Assertion A: Polluted water may have a value of BOD of the order of \( 17 \) ppm.Reason R: BOD is measure of oxygen required to oxidise both the biodegradable and non-biodegradable organic material in water.In the light of the above statements, choose the most appropriate answer from the options given below.
The deposition of \( X \) and \( Y \) on ground surfaces is referred as wet and dry depositions, respectively. \( X \) and \( Y \) are:
Given below are two statements:Statement I: If BOD is \( 4 \, \text{ppm} \) and dissolved oxygen is \( 8 \, \text{ppm} \), then it is a good quality water.Statement II: If the concentration of zinc and nitrate salts are \( 5 \, \text{ppm} \) each, then it can be a good quality water.In the light of the above statements, choose the most appropriate answer from the options given below:
The concentration of dissolved Oxygen in water for growth of fish should be more than $\underline{\text{X}}$ ppm and Biochemical Oxygen Demand in clean water should be less than $\underline{\text{Y}}$ ppm. $\text{X}$ and $\text{Y}$ in ppm are, respectively.
Some reactions of \( \mathrm{NO_2} \) relevant to photochemical smog formation are:Identify \( A \), \( B \), \( X \) and \( Y \).
The statements that are TRUE:(A) methane leads to both global warming and photochemical smog(B) methane is generated from paddy fields(C) methane is a stronger global warming gas than \( \mathrm{CO_2} \)(D) methane is a part of reducing smogChoose the most appropriate answer from the options given below:
Correct statement is:
Given below are two statements:Statement I: Non-biodegradable wastes are generated by the thermal power plantsStatement II: Bio-degradable detergents leads to eutrophication.In the light of the above statements, choose the most appropriate answer from the options given below:
Given below are two statements:Statement I: Chlorofluoro carbons breakdown by radiation in the visible energy region and release chlorine gas in the atmosphere which then reacts with stratospheric ozone.Statement II: Atmospheric ozone reacts with nitric oxide to give nitrogen and oxygen gases, which add to the atmosphere.For the above statements choose the correct answer from the options given below:
The acid that is believed to be mainly responsible for the damage of Taj Mahal is:
Which of the following statements is NOT correct ?
The industrial activity held least responsible for global warming is:
Which of the following compounds is an example of Freon?
The photochemical smog does not generally contain:
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 \( 6.5 \, \text{ppm} \)In the light of the above statements, choose the most appropriate answer from the options given below