Mystery #4Tier 1-2food / heat / pressure
Why does a hard little corn kernel explode into fluffy popcorn?
A popcorn kernel starts out as a hard little pebble you could not bite through. Heat it up and it suddenly explodes, flipping itself inside out into a soft white puff many times bigger than before, with a loud pop. Something small and hard becomes something big and fluffy in a heartbeat. What on earth is going on inside?
Your guess
What's your hunch: what's hiding inside that makes the kernel burst?
There's no single magic word to type, have a go in your own words, then reveal the answer to see how close you got.
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