Multiple Choice Questions (MCQ) on Environment Science

Multiple Choice Questions (MCQ) on Environment Science

1- Which of the following air pollutants is/are responsible for photochemical smog?

(A) Oxides of nitrogen, unburnt hydrocarbons, and Sunlight

(B) Ozone, oxides of nitrogen and unburnt hydrocarbons

(C) Oxides of nitrogen and carbon monoxide

(D) None of the above


2- The atmosphere around Earth is warmed because

(A) plants release carbon dioxide

(B) fossil fuels release heat

(C) molecules in the atmosphere are warmed by radiation from Earth and retained

(D) None of these


3- Which one of the following sets of processes is a part of self-purification of streams?

(A) Settling, bio-degradation and desalination

(B) Flotation, ion exchange and desalination

(C) Settling, bio-degradation and aeration

(D) None of the above


4- In a typical troposphere, air temperature decreases with height at the following rate:

(A) 2.5 degree C per one kilometer

(B) 6.5 degree C per one kilometer

(C) 4.5 degree C per one kilometer

(D) 12.5 degree C per one kilometer


5- Consider the following statements regarding harmful effects of certain air pollutant

  1. Low productivity in plants
  2. Participates in acid rain
  3. Irritation in eyes and lungs

Which of the following pollutant has above harmful effects?

(A) Particulate matter

(B) Nitrogen compounds

(C) Carbon compounds

(D) Hydrocarbons


6- Which procedure of wastewater treatment takes place without oxygen?

(A) Degradation of dissolved organic carbon compounds

(B) Nitrification

(C) Release of phosphates for the production of energy

(D) Denitrification


7- The darker zone in lakes, where light penetration is negligible is called:

(A) Limnetic zone

(B) Profundal zone

(C) Littoral zone

(D) Euphotic zone


8- Which of the following appears to contribute to global cooling rather than global warming?

(A) nitrous oxide

(B) CFCs

(C) methane

(D) None of the above


9- A technique used to determine the concentration of odour compounds in a sample is known as

(A) Chlorination

(B) Settling

(C) Flushing

(D) Stripping


10- If a fresh water sample’s total alkalinity is higher than the total hardness, it indicates that:

(A) some hardness is in the bicarbonate form

(B) all hardness is in the bicarbonate form

(C) no hardness is in the bicarbonate form

(D) all hardness is in the carbonate form



1-(A), 2-(C), 3-(C), 4-(B), 5-(B), 6-(C), 7-(B), 8-(D), 9-(D), 10-(D)