Lesson 42 of 84 · Matter

Experiment⭐ 30 XP🧪 Potion Kitchen

Reversible or Not? (Part 2)

🧪Lab Brief #42

Reversible or Not? (Part 2).

🎯 Your mission

Predict it first. Then prove yourself right (or wrong).

⚡ The twist

Mixing two safe things doesn't always make a safe thing.

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Mind = Blown

💧 Hot water can freeze faster than cold water under the right conditions. Nobody fully understands why.

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Make a hypothesis first

Predict: will the mixture get hotter, colder, or stay the same?

What You'll Learn

Some changes can be reversed (melting ice) and some cannot (baking a cake).

Key Words

Tap a word to see its definition.

Materials Needed

ice cubes
salt
sugar
vinegar
baking soda

Safety First

Wear safety goggles when mixing liquids.
Wash hands after handling materials.
Be careful with scissors — ask an adult for help if needed.

Steps

Step 1 — Read

Look at the new words. Can you say each one?

Step 2 — Do

Put an ice cube on a plate and watch it for 10 minutes. Draw what it looks like every 2 minutes.

Step 3 — Observe

Use your senses to describe what you notice.

Step 4 — Record

Write 1-2 sentences about what happened.

Check Your Understanding

Question 1

1 of 3

What happens when you mix baking soda and vinegar?

How sure are you going to be?😐 maybe

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Where you see this in real life

Your toothpaste, your soap, even your breakfast involves this.

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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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Next Smart Experiment

We'll pick an experiment that matches exactly how you're thinking right now.

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Send it to a parent who's looking for a 10-minute kitchen science win.

🖨️

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