The Loudest Non-Reaction in the Kitchen

You'll learnthe one question that separates a physical change from a chemical one, and why bubbles and heat never answer it.

Boiling water hisses, bubbles from the bottom up and pours off gas, and nothing has reacted. Rusting iron does nothing visible for a month and is chemical the whole time. One question sorts them both. Twelve short steps; press Next for each one.

12 STEPS · 6 QUICK CHECKS · ONE TEST, NOT FOUR CLUES · v4

bubbles · heat · colour · and the one question that decides

Before you start

What you're looking at

A box of water molecules, and a stamp underneath reading physical or chemical.

The question

Boiling water bubbles harder than most reactions. Is it one?

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