Water Pollution
25 Grade 5 Integrated Science questions on Water Pollution, with worked marking schemes. 25 questions are available on this topic in full.
Question 1
3 marks(a) What is meant by water pollution?
(b) State two human activities that cause water pollution.
(3 marks)
Marking scheme
(a) Adding harmful or dirty substances to water, making it unsafe for use (1 mark). (b) Any two: dumping rubbish/waste into water; releasing factory waste; letting sewage flow into rivers; farm chemicals washing into water; oil spills; washing/bathing in water sources (2 marks).
Question 2
1 markWhich of the following is the best way to prevent water pollution in your area?
A. pouring used oil into the drain
B. washing cars in the river
C. dumping all waste into the river
D. disposing of waste in a proper pit or dustbin
(1 mark)
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1 markPolluted water can cause
A. good health
B. waterborne diseases like cholera and typhoid
C. strong teeth
D. clear eyesight
(1 mark)
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1 markWhich of the following activities pollutes water?
A. Building dams
B. Harvesting rainwater
C. Spraying pesticides near rivers
D. Planting trees along riverbanks
(1 mark)
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1 markWe need clean water in our homes mainly for ___.
A. drinking, cooking and washing
B. killing fish in the river
C. polluting the environment
D. spreading diseases in the home
(1 mark)
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1 markWhich one of the following is a safe way of protecting a water source?
A. washing clothes in the water source
B. throwing dead animals into the river
C. planting trees and grass along the river bank
D. grazing many animals inside the river
(1 mark)
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1 markWhen oil spills into a lake it mainly harms the fish because ___.
A. it stops air (oxygen) from reaching the water
B. it adds more food for the fish
C. it makes the water sweeter
D. it cools the water for the fish
(1 mark)
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1 markChemicals such as pesticides used on a farm can pollute a nearby river when they are ___.
A. washed into the river by rain
B. sprayed on a calm day
C. used up completely by the plants
D. kept safely in a store
(1 mark)
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1 markRaw sewage that flows into a river is a source of water pollution because ___.
A. it adds clean minerals to the water
B. it makes the water safe to drink
C. it adds germs and human waste to the water
D. it removes rubbish from the water
(1 mark)
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1 markWhen a river becomes heavily polluted, water animals such as fish may ___.
A. grow faster and bigger
B. change into insects
C. die due to lack of clean water and oxygen
D. produce more eggs than usual
(1 mark)
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Create a free account to see itQuestion 11
3 marksA farmer sprays pesticides on crops growing close to a river.
(a) Explain how this can pollute the river.
(b) Give two pieces of advice you would give to the farmer.
(3 marks)
Marking scheme
(a) When it rains, the chemicals are washed from the farm into the river (1 mark). (b) Any two: leave a strip of land (buffer) between the farm and the river; use less chemicals or use organic manure instead; do not spray close to the river (2 marks).
Question 12
1 markWhich of the following is a water pollutant?
A. Fresh air
B. Sunlight
C. Clean rain
D. Factory chemicals
(1 mark)
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Create a free account to see itQuestion 13
4 marksA factory near River Nyando releases its waste directly into the river. Villagers downstream use this water for their homes.
(a) State two problems the villagers may face.
(b) Suggest two ways the problem can be solved.
(4 marks)
Marking scheme
(a) Any two: they may get waterborne diseases such as cholera or typhoid; they lack clean water for use; fish and water animals die; they may get skin problems (2 marks). (b) Any two: the factory should treat its waste before releasing it; report the factory to the authorities/NEMA; provide the villagers with an alternative clean water source; build waste treatment ponds (2 marks).
Question 14
1 markWhich of the following activities pollutes river water?
A. building a fence far from the river
B. planting trees along the river bank
C. fetching water in clean containers
D. throwing rubbish and waste into the river
(1 mark)
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1 markWater pollution means ___.
A. boiling water before drinking
B. storing water in a clean tank
C. adding harmful substances to water
D. making water clean and safe for use
(1 mark)
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4 marksState four ways in which water pollution can be prevented in your community.
(4 marks)
Marking scheme
Award 1 mark each for any four: dispose of waste properly (pits/dustbins); treat factory and sewage waste before release; avoid dumping rubbish in rivers; plant trees and grass along river banks; do not wash cars or clothes in water sources; educate people on keeping water clean. (4 marks)
Question 17
3 marksExplain how water pollution affects the animals and plants that live in water.
(3 marks)
Marking scheme
Award 1 mark each for any three: it reduces the oxygen in the water so fish and other animals die; harmful chemicals poison the water animals and plants; it kills water plants; it destroys their habitat/breeding grounds and reduces their food. (3 marks)
Question 18
1 markWater pollution is caused by
A. cleaning water sources
B. conserving water
C. planting trees near rivers
D. dumping waste into rivers and lakes
(1 mark)
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1 markOil spills in the ocean are harmful because they
A. help fish grow faster
B. improve water quality
C. make the ocean cleaner
D. kill fish and other marine life
(1 mark)
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1 markThe best way to get rid of used plastic bottles is to ___.
A. collect and recycle them
B. leave them on the river bank
C. bury them in the river bed
D. throw them into the river
(1 mark)
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1 markDrinking water that has been polluted with human waste can cause ___.
A. a toothache
B. a broken leg
C. cholera
D. malaria
(1 mark)
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4 marks(a) State two uses of clean water in the home.
(b) Give two reasons why we should keep our water sources clean.
(4 marks)
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1 markTo prevent water pollution, we should
A. avoid dumping waste in water sources
B. wash clothes in rivers
C. pour chemicals into streams
D. throw rubbish into lakes
(1 mark)
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2 marksYour class is making a poster to encourage people to protect water sources. Write two messages you would put on the poster.
(2 marks)
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4 marks(a) Name two diseases that people can get from drinking polluted water.
(b) State two ways of making water safe for drinking.
(4 marks)
Marking scheme
(a) Any two: cholera, typhoid, dysentery, diarrhoea, bilharzia (2 marks). (b) Any two: boil the water; treat it with chemicals such as chlorine/water-treatment tablets; filter the water; store it in a clean covered container (2 marks).
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