Hot Ice (Sodium Acetate)
A clear liquid freezes solid the instant you touch it — crystallisation on command.
Start building ↓The build
React & boil down
Combine vinegar and soda, then simmer to a syrup.
Cool gently
Chill the clear solution undisturbed.
Touch to trigger
Drop in a seed crystal or touch the surface.
Build towers
It freezes into warm solid 'ice' as you pour.
The cooled solution is supersaturated; a seed gives molecules a template to snap into a crystal lattice all at once, releasing heat.
A closer look
Crystallisation of supersaturated sodium acetate is exothermic, so the 'ice' is actually warm — the same as reusable hand warmers.
Variables to test
- 1 Pour onto a seed — build a growing tower.
- 2 Feel the temperature — why is the 'ice' warm?
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