Thermal pollution of water increases its toxicit and oxidation of oxygen demanding waste besides favouring bacterial growth. A rise in water temperature by 10°C, doubles the toxic effects of _________ present in it

10. Thermal pollution of water increases its toxicit and oxidation of oxygen demanding waste besides favouring bacterial growth. A rise in water temperature by 10°C, doubles the toxic effects of _________ present in it
o potassium cyanide
o ortho-xylene
o coal ash
o none ofthese



Ans: A

Atmospheric pollution caused by the exhaust gas of supresonic transport air-crafts is mostly in the atmospheric region called

9. Atmospheric pollution caused by the exhaust gas of supresonic transport air-crafts is mostly in the atmospheric region called 
o stratosphere
o mesosphere
o thermosphere
o troposphere

Ans: A


Ambient noise level can be reduced by _______ decibels by planting trees like coconut, neem etc.) near public utilit buildings (like hospitals & schools)

8. Ambient noise level can be reduced by _______ decibels by planting trees like coconut, neem etc.) near public utilit buildings (like hospitals & schools)
o 1-2
o 5-10
o 25-30
o 35-40

Ans: B

A shallow pond in which the sewage is retained and biologically treated is called

7. A shallow pond in which the sewage is retained and biologically treated is called
o oxidation
o lagoon
o Imhoff tank
o skimming tank

Ans: A

Maximum permissible turbidity in potable water is _______ ppm

6. Maximum permissible turbidity in potable water is _______ ppm
o 1
o 10
o 250
a 1000

Ans: B

Pick out the %Tong statement

5. Pick out the %Tong statement
o Decomposition of plants containing chlorophyll is a natural source of carbon monoxide in atmosphere
o Catalytic converter is fitted in automobiles to reduce carbon monoxide concentration in exhaust emissions
o Inhalation of pollutant carbon monoxide results in death by asphyxiation
o Sulphur dioxide is the main pollutant emitted from the exhaust of petrol driven automobiles

Ans: D

The amount of chemical coagulant added for treatment of polluted water ________ with increase in temperature of the polluted water to be treated

4. The amount of chemical coagulant added for treatment of polluted water ________ with increase in temperature of the polluted water to be treated 
o may increase or decrease : depends on the chemical characteristics of polluted water
o increases
o remains constant
o decreases

Ans: D