Lesson 83 of 84 · Chemical Reactions
Experiment⭐ 30 XP🧪 Potion KitchenConservation of Mass (Part 3)
Chemical Reactions.
🎯 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
Conservation of mass means that matter cannot be created or destroyed in a chemical reaction. If you start with 10 grams of reactants, you end with 10 grams of products.
Key Words
- chemical bond
- molecular formula
- pH
Materials Needed
- thermometer
- strainer
- ice cubes
Safety First
- Handle glass items carefully to avoid breakage.
- Do not mix unknown chemicals together.
Steps
Read the introduction and identify the main idea of this lesson.
Test 5 household liquids (vinegar, milk, lemon juice, baking soda water, soap) with pH paper. Classify each as acid, base, or neutral.
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 does conservation of mass mean?
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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