Water Science
What happens to most substances when they freeze? What does water do instead?
Most contract; water expands.
True or False: Hot water can freeze faster than cold water.
True (the Mpemba effect).
What does “anomalous” mean?
Unusual or deviating from the norm.
If water didn’t expand when it froze, how might winter ecosystems be different?
Lakes and rivers would freeze solid, killing aquatic life.
What percentage of Earth’s surface is covered in water?
About 71%.
Why does water have a stabilizing effect on climate?
Because it has a high heat capacity.
What is the only substance on Earth naturally found in solid, liquid, and gas forms?
Water
Give a synonym for “capacity” as used in the article.
Ability, potential, or volume.
Imagine a planet where water evaporates very quickly. What would happen to animals there?
They would dehydrate faster and struggle to stay cool.
What is the process by which plants release water into the air?
Transpiration.
What is one reason ice floating is important for life?
It insulates lakes, allowing aquatic life to survive under the surface.
Why does water behave unusually when it reaches 4°C?
That’s when it reaches its maximum density—colder water becomes less dense.
What does “insulate” mean in the context of water and ice?
To protect or shield from temperature change.
If you were designing a robot to live in the ocean, what water property would be most important to consider?
Density, pressure, or temperature stability.
What’s one way water helps regulate Earth’s temperature?
Oceans absorb and store heat.
What is cohesion in water, and what causes it?
The attraction between water molecules caused by hydrogen bonding.
What would happen to aquatic life if ice sank instead of floated?
Lakes and oceans would freeze solid, killing life below.
Use the word “evaporation” in a sentence about the human body.
(Student-generated – e.g., "Sweating cools the body through evaporation.")
Why might desert animals have special adaptations related to water’s heat capacity?
To store water or regulate body temperature despite extreme conditions.
Name one ecosystem that depends heavily on water’s anomalous behavior.
Wetlands, oceans, polar lakes, etc.
What property of water makes sweating an effective cooling mechanism?
Its high heat of evaporation.
What’s the term for animals that walk on water thanks to surface tension?
Water striders.
What does “density” mean, and why is it important for understanding water's behavior?
Mass per unit volume; it explains why ice floats and water sinks.
Design a new water-based life form. What feature of water would it use to survive?
(Open-ended—students must justify answers using science from the text.)
Why do coastal areas usually have milder climates than inland regions?
Water absorbs heat slowly and releases it slowly, moderating temperatures.