Water Pollutants

Q.

Which of the following statements about eutrophication are correct?

(i) It can be a naturally occurring process.

(ii) It commonly occurs in stagnant rather than running water.

(iii) It does not affect oxygen level of water bodies.

(iv) It is commonly associated with high levels of phosphates and nitrates.

1. i, ii and iv
2. i, ii and iii
3. ii, iii and iv
4. all of these

Q. Read the following statements related to eutrophication and select the correct option stating true (T) and false (F).

A. It is the process of aging of water bodies due to the excessive growth of algae, plants and other aquatic organisms.
B. It can be natural or accelerated.
C. Accelerated eutrophication occurs at a slow rate which cannot be predicted.
D. The prime contaminants for this phenomenon are nitrates and phosphates.

1. A - T, B - T, C - F, D - T
2. A - T, B - F, C - F, D - T
3. A - T, B - F, C - T, D - F
4. A - T, B - T, C - F, D - F

Q. Limit of BOD prescribed by Central Pollution Control Board for the discharge of industrial and municipal wastewater into natural surface water is

1. <10 ppm
2. <100 ppm
3. <30 ppm
4. <3.0 ppm

Q. In which one of the following the BOD (Biochemical Oxygen Demand) of sewage (S), distillery effluent (DE), paper mill effluent (PE) and sugar mill effluent (SE) have been arranged in ascending order?

1. SE < PE < S < DE
2. PE < S < SE < DE
3. S < DE < PE < SE
4. SE < S < PE < DE

Q. Which element is responsible for causing soil salinity? At what concentration does the soil become saline?

Q. Which of the following is not a heavy metal found in the industrial wastewater?

1. Copper
2. Lead
3. Cadmium
4. Sodium

Q. Which of the following metals is a water pollutant?

1. As
2. Mn
3. Mg
4. Hg

Q. Contamination of water by arsenic and fluoride is a major problem in India due to

1. deforestation
2. water scarcity
3. global warming
4. dumping of plastic

Q.

Write critical notes on the following:

(a) Eutrophication

(b) Biological magnification

(c) Groundwater depletion and ways for its replenishment

Q. Which is not a bioindicator of water pollution?

1. Blood worms
2. Stone flies
3. Sludge worms
4. Sewage fungus

Q. Eutrophication is a type of

1. Air pollution
2. Noise pollution
3. Land pollution
4. Water pollution

Q. Match the items given in Column I with those in Column Il and select the correct option given below.

Column I	Column II
p. Eutrophication	i. Shielded containers
q. Sanitary landfills	ii. Organic farming
r. Radioactive waste	iii. Nutrient enrichment
s. Compost	iv. Waste disposal

1. p-i, q-iii, r- iv, s –ii
2. p-ii, q-i, r- iii, s –iv
3. p-i, q-ii, r- iv, s –iii
4. p-iii, q-iv, r- i, s –ii

Q. Minamata and itai itai disease are due to toxicity of

1. Mercury and tin
2. Mercury and cadmium
3. Mercury and lead
4. Mercury and strontium

Q. What are the benefits of household waste water recycling systems?

Q. Read the following statements and choose the correct answer.
Assertion: The use of agrochemicals and improved crop varieties led to the Green Revolution.
Reason: One of the major cons of Green revolution was the degradation of the environment.

Q. Water pollution act defines

1. Water pollution and water quality standards
2. Noise pollution
3. Air pollution and water quality standards
4. None of the above

Q. Oil spills cause water pollution in rivers.

1. True
2. False

Q. Excessive accumulation of organic matter in water bodies leads to:

1. Green house effect.
2. Decrease in species diversity.
3. No effect on species diversity.
4. Increase in species diversity.

Q. Minamata disease is caused by

1. Chromium
2. Cadmium
3. Methylmercury
4. Radioactive elements

Q. Which one of the following is not a bioindicator of water pollution?

1. Sludge-worms
2. Blood-worms
3. Stone flies
4. Sewage fungus

Q. What is algal bloom. How does it affect the lakes?

Q. List any four factors which determine the amount of dissolved oxygen in water. Explain in brief the harmful effects of nitrate, fluoride and arsenic salts in ground water on humans.

Q. Which one of the following is called as indicator species for polluted waters?

1. Tubifex
2. Phytoplanktons
3. Zooplanktons
4. Prawns

Q. Dissolved oxygen in water decreases with an increase in the temperature of the water.

1. False
2. True

Q.

Write critical notes on the following:

(a) Eutrophication

(b) Biological magnification

(c) Groundwater depletion and ways for its replenishment

Q.

Minamata disease is caused due to the presence of______in water.

1. Cadmium

2. Lead

3. Arsenic

4. ​​​​​​Mercury

Q. Which metal causes minamata disease?

1. Lead
2. Manganese
3. Mercury
4. Copper

Q. Give reasons.

Oil spill adversely affects the aquatic life.

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

1. True
2. False

Q.

A major threat to ocean life comes from

1. Disposal of sewage

2. Oil spillage due to tanker accidents

3. Acid rains

4. Garbage disposal by ships