Lesson 4 of 84 · Chemical Reactions
Lesson⭐ 30 XP🧪 Potion KitchenChanging States: Melting and Freezing
Chemical Reactions.
🎯 Your mission
Understand the idea. Then look for it everywhere.
⚡ The twist
Mixing two safe things doesn't always make a safe thing.
Mind = Blown
🌈 Every color you see is your brain inventing a translation of light frequencies.
Make a hypothesis first
Predict: will the mixture get hotter, colder, or stay the same?
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
Steps
Review the background information on Chemical Reactions 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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