Water Purification 1
This method of water purification uses heat to kill germs.
Boiling
These harmful organisms in contaminated water can cause disease.
Answer: Bacteria, viruses, and parasites
This process makes water clean and safe for use.
Answer: Purification
This process changes liquid water into water vapour using heat from the sun.
Evaporation
This form of precipitation falls as frozen ice crystals.
Answer: Snow
This chemical is added to water to kill germs.
Answer: Chlorine
This type of pollution happens when harmful substances enter water sources.
Water pollution
How does agricultural activities lead to water pollution?
Fertilizers and pesticides washing into rivers.
This stage of the water cycle forms clouds.
Answer: Condensation
During condensation, water vapour changes into this state of matter.
Answer: Liquid
This disease can spread through contaminated drinking water and causes severe diarrhoea and dehydration.
Cholera
This form of purification uses sunlight and ultraviolet rays to destroy germs.
Answer: Solar disinfection
These two groups of people are especially at risk from waterborne illnesses.
Answer: Children and the elderly
Water falling from clouds as rain is called this.
Answer: Precipitation
Explain why evaporation occurs more rapidly on hot days.
Answer: Heat energy from the sun increases the rate of evaporation
Water passing through cloth, sand, or commercial filters is an example of this purification method.
Answer: Filtration
Why should you boil water for more than just a few seconds?
Answer: Germs need to be exposed to high temperatures before they die.
State two ways people can help prevent water pollution in their communities.
Answer varies
State one importance of the water cycle to living organisms.
Answer: It supplies fresh water needed for life
Explain why conserving water is important during dry seasons.
Answer: Water supplies may become limited and shortages can occur
Explain one advantage of solar disinfection in rural communities.
Answer: It uses free sunlight and does not require electricity
State two dangers of drinking contaminated water.
Answer: Spread of diseases and chemical poisoning
Explain why filters alone may not completely purify water.
Answer: Some microorganisms and chemicals may still remain
Explain three ways humans use water in the home besides drinking.
Answer: Cooking, bathing, washing, cleaning, water plants
Explain how flooding can contaminate water supplies.
Answer: Floodwater may carry sewage, garbage, and chemicals into clean water sources