Lesson 4 of 84 · Matter and Atoms
Experiment⭐ 30 XP🧪 Potion KitchenChanging States: Melting and Freezing
Matter and Atoms.
🎯 Your mission
Run the experiment. Find out what really happens.
⚡ The twist
If it bubbles, something invisible is escaping.
Mind = Blown
💧 Hot water can freeze faster than cold water under the right conditions. Nobody fully understands why.
Make a hypothesis first
Guess: will the fizz be loud, soft, or none at all?
What You'll Learn
Physical changes alter the appearance of matter without changing its chemical identity. Cutting paper, melting ice, and dissolving sugar are all physical changes.
Key Words
- proton
- neutron
- electron
Materials Needed
- ice cubes
- salt
- sugar
Safety First
- Use materials only as directed in the experiment.
- Keep small objects away from young children.
Steps
Review the background information on Matter and Atoms before starting.
Heat ice and record the temperature every minute as it melts and then boils. Graph the temperature changes and label each phase change.
Look for patterns in your observations.
Make a graph or chart showing your results.
Check Your Understanding
Question 1
1 of 3Which is an example of a chemical change?
Where you see this in real life
Your toothpaste, your soap, even your breakfast involves this.
Stretch Challenge
Try this in real life this week.
Ask a grown-up to help you mix two safe kitchen things. Predict what will happen first.
For the dinner table
“What's something we cook that mixes things together this way?”
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