Questions
Which of the following are the causes of water pollution?
(i) Defecating in water bodies
(ii) Disposing off idols of gods and goddesses into water bodies
(iii) Discharging industrial wastes into water bodies
(iv) Growth of phytoplankton in water bodies
- (i), (ii) and (iii)
- (i) and (ii)
- (i), (iii) and (iv)
- (ii) and (iii)
Which of the following methods is not used to make water safe for drinking?
- Filteration
- Sedimentation
- Boiling
- Chlorination
Which of the following diseases is caused due to water pollution?
- Cholera
- Malaria
- Asthma
- Cough
Which of the following diseases is not caused by polluted water?
- Cholera
- Jaundice
- Typhoid
- Asthma
The anomalous expansion of water can be observed in the temperature range of
- 0 K to 4 K
- 0oC to 4oC
- -4oC to 0oC
- -4oC to 6oC
In which of the following situations is the anomalous expansion of water beneficial?
- Cooking of food in a pressure cooker
- Freezing of water in a refrigerator
- Freezing of water bodies in cold areas
- Evaporation of water from the surface of water bodies
How is the growth of algae in water bodies harmful to aquatic organisms?
- It releases poisonous chemicals in water bodies.
- It decreases oxygen level in water bodies.
- It increases CO2 level in water bodies.
- It increases the temperature of water bodies.
Which of the following chemicals / substances, when added to a settling tank, fastens the process of sedimentation?
- Washing soda
- Potash alum
- Quartz
- Silica
How is the growth of algae in water bodies harmful to aquatic organisms?
- It releases poisonous chemicals in water bodies.
- It decreases oxygen level in water bodies.
- It increases CO2 level in water bodies.
- It increases the temperature of water bodies.
Which of the following is not a water pollutant?
- Sewage
- Toxic chemical
- Silt
- Smoke