Lesson 47 of 84 · Chemical Reactions
Lesson⭐ 30 XP🧪 Potion KitchenPhysical vs Chemical Changes (Part 2)
Chemical Reactions.
🎯 Your mission
Learn the rule. Then catch nature using it.
⚡ 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
Chemical changes produce new substances with different properties. Signs of a chemical change include color change, gas production, temperature change, and formation of a precipitate.
Key Words
- chemical bond
- molecular formula
Steps
Look at the vocabulary words and write a definition for each in your own words.
Heat ice and record the temperature every minute as it melts and then boils. Graph the temperature changes and label each phase change.
Draw a detailed diagram of what you observe.
Write a conclusion: what did your results show? Did they match your prediction?
Check Your Understanding
Question 1
1 of 3What makes a physical change different from a chemical change?
Where you see this in real life
This is happening in your kitchen right now — every time food cooks.
Stretch Challenge
Try this in real life this week.
Find one ingredient in a snack and look up what it does.
For the dinner table
“What's something we cook that mixes things together this way?”
Next Smart Experiment
We'll pick an experiment that matches exactly how you're thinking right now.
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