Lesson 27 of 84 · Earth Systems
Experiment⭐ 30 XP🌋 Rock RealmCaves and Sinkholes
Earth Systems.
🎯 Your mission
Run the experiment. Find out what really happens.
⚡ The twist
Weather isn't random — it's just complicated.
Mind = Blown
🌊 The deepest part of the ocean is deeper than Mount Everest is tall.
Make a hypothesis first
Before you observe: what shape will it leave?
What You'll Learn
Sinkholes form when underground limestone dissolves, leaving a cavity that collapses. They are common in areas with karst topography where water slowly dissolves the bedrock.
Key Words
- evaporation
- condensation
Materials Needed
- water
- plastic tray
- magnifying glass
Safety First
- Do not taste any materials.
- Wear safety goggles when mixing liquids.
Steps
Look at the vocabulary words and write a definition for each in your own words.
Test rock hardness using Mohs scale: try scratching rocks with your fingernail, a penny, and a nail. Rank them from softest to hardest.
Compare the before and after states.
Write your conclusion: did the results match your hypothesis? What would you change next time?
Check Your Understanding
Question 1
1 of 3What causes ocean tides?
Where you see this in real life
Today's weather, tomorrow's beach, next century's coastline — all this.
Stretch Challenge
Try this in real life this week.
Look at the sky for 5 minutes and try to predict tomorrow's weather.
For the dinner table
“What's the slowest change you can think of?”
Next Smart Experiment
We'll pick an experiment that matches exactly how you're thinking right now.
Share this experiment
Send it to a parent who's looking for a 10-minute kitchen science win.
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