Water Systems
Define Potable Water
Water that is safe to drink
What does the pH scale indicate about a substance?
How acidic or basic it is.
Identify one human activity that contributes to water pollution
Examples: oil spills, sewage, industrial waste, fertilizers.
What is the purpose of adding chlorine or ozone during water treatment?
To kill bacteria and disinfect the water.
What is an ecological footprint?
A measure of how much of Earth’s resources a person uses.
Explain why not all freshwater is considered potable.
Freshwater may contain bacteria, chemicals, or pollutants, so it must be treated to become potable.
Explain what is meant by brine water.
Water with a very high concentration of dissolved salt.
Explain how agricultural rain runoff affects water quality.
Chemicals wash into water, causing pollution and harming organisms.
Explain the role of coagulation and flocculation.
Coagulation causes particles to stick together; flocculation forms larger clumps (floc) for removal.
Why might clear, odourless water still be unsafe?
It may contain invisible contaminants like bacteria or chemicals.
Describe two factors that can limit access to usable freshwater even if water is present in a region.
Examples: pollution, lack of infrastructure, uneven distribution, drought (must explain).
Why is high salinity harmful to both some plants and aquatic organisms?
Salt removes water from cells (osmosis), causing dehydration and death.
Acid rain was more common in the 1970s and 1980s than it is today. Explain why this was the case and how human actions contributed to it.
Higher levels of air pollution from factories and burning fossil fuels released sulfur dioxide and nitrogen oxides. These gases mixed with water vapour to form acid rain. Regulations and cleaner technologies have since reduced these emissions.
Why is filtration alone not enough to make water potable?
It removes particles/sediments but not bacteria or dissolved contaminants.
Describe one individual action to reduce water scarcity and its impact.
Example: turning off taps reduces water use and conserves supply.
Explain how overuse of groundwater (aquifers) can lead to long-term water scarcity.
Water is removed faster than it is replenished, causing water levels to drop and shortages over time.
On the pH scale, approximately what pH value would you expect for lemon juice?
Around 2 (strongly acidic)
Explain how both physical factors and social factors contribute to long-term water advisories in some First Nations communities.
Explain one limitation of desalination.
Expensive, energy-intensive, or not practical inland.
Bioremediation is the process of using what to break down hazardous materials in soil or water.
microorganisms
A country has large freshwater lakes but still experiences water shortages. Provide two reasons and explain each.
Examples: water is polluted, lack of treatment systems, unequal access, seasonal shortages.
A student evaporates 1 litre of seawater. Predict how much solid salt will remain and explain your reasoning.
About 35 grams, because the water evaporates and leaves the dissolved salt behind.
A community dumps waste into a nearby river. Describe one environmental impact and one human impact this could have.
A coastal city must choose between desalination and conservation. Which is more sustainable? Explain.
Conservation is generally more sustainable (less energy, lower cost long-term), though desalination provides supply.
A home has perfectly clear water but experiences clogged pipes over time. Predict the cause of the issue and explain how a water softener would help.