Water Pollution

Q.

Chemical formula of Water-gas is:

1. $C{O}_2+H_{2}O$
2. $CO+H_2$
3. $S{O}_2+C{O}_2+Heat$
4. $CO+H_2{O}_2$

Q.

Biochemical oxygen demand is a measure of organic material present in water. BOD value less than 5ppm indicates a water sample to be ___________.

1. Rich in dissolved oxygen.

2. Poor in dissolved oxygen.

3. Highly polluted.

4. Not suitable for aquatic life.

Q.

Name the chemical used to kill germs in water

Q.

Sewage containing organic waste should not be disposed in water bodies because it causes major water pollution.Fishes in such a polluted water die because __________

1. Increase in amount of dissolved oxygen

2. Decrease in amount of dissolved oxygen in water

3. Clogging of gills by mud

4. Large number of mosquitoes

Q.

Based on the statements given here choose the correct answer.
(1) In polar regions aquatic life is safe in water under frozen ice.
(2) Water has a high latent heat of fusion and the upper portion of ice does not allow the heat of the water to escape to the surroundings.

1. Only (1) is true.

2. (1) and (2) are true and (2) explains (1).

3. Only (2) is true.

4. (1) and (2) are true but (2) does not explain (1).

Q.

Chemical formula of Water-gas is:

1. $C{O}_2+H_{2}O$
2. $CO+H_2$
3. $S{O}_2+C{O}_2+Heat$
4. $CO+H_2{O}_2$

Q. Dumping untreated sewage into water leads to:

1. air contamination
2. water contamination
3. water filtration
4. water conservation

Q.

Question 3
Do you know of any activity which may be polluting the water source?

Q. What is waste water treatment?

1. Treatment of contaminated water for drinking purposes only
2. Reuse of water
3. Treatment of water so that it enters the water cycle or reused
4. All of above

Q. Statement A: Human beings can exist without clean water.
Statement B: Water that we use should be clean.

1. Only statement A is true
2. Only statement B is true
3. Both statement A and statement B are true
4. Both statement A and statement B are false

Q. A fish survives in water because of the dissolved oxygen present in it.

1. True
2. False

Q. All solutions are mixtures, but not all mixtures are solutions.

1. True
2. False

Q.

Name the gas used to disinfect filtered water.

Q. Sewage waste contains mainly water.

1. True
2. False

Q. Match each process in a wastewater treatment plant with the substance that gets removed during it.

1. Grit removal
2. Screening
3. Sedimentation
4. Plastic bags
5. Pebbles & sand
6. Sludge

Q. Oil spills are the only source of water pollutants in ocean water.

1. True
2. False

Q. Oil spill prevention and clean up procedures are monitored by

1. Navy officers
2. Environmentalist
3. Coast guards
4. None of the above

Q. Sewage waste contains mainly water.

1. False
2. True

Q. Naphthalene balls disappear after a while when left open. The phenomenon responsible for this process is:​

1. Deposition
2. Sublimation
3. Melting
4. Evaporation

Q. The dumping of which of the following items in water bodies can cause a health hazard?

1. Plastic
2. Cooking oil
3. Human waste
4. Paint

Q. Read the following statements.
A. A few rivers in India are like sewers.
B. Some cattle may die by feeding on plastic bags.
C. Installation of wastewater treatment plants has cleaned up most of the rivers in India.
D. Sludge is effectively utilized in the production of biogas.
Select the option which includes all correct statements.

1. A, B and C
2. A, B and D
3. B, C and D
4. A, C and D

Q. Match the waste to its respective source.

1. Soaps and detergents
2. Scrap metals and ash
3. Fertilisers
4. Vegetables