Lesson 62 of 84 · Chemical Reactions
Lesson⭐ 30 XP🧪 Potion KitchenPhase Changes in Everyday Life (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
The law of definite proportions states that a compound always contains the same elements in the same ratio by mass. Water is always 11.2% hydrogen and 88.8% oxygen.
Key Words
- product
- conservation of mass
- solubility
Steps
Look at the vocabulary words and write a definition for each in your own words.
Create a density column: carefully layer honey, dish soap, water, vegetable oil, and rubbing alcohol in a tall glass. Drop small objects in to test where they float.
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 3Which is a sign of 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?”
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