Probably sodium acetate. Dissolve it in near-boiling water (to supersaturate the solution) until no more can be added, then let it cool back to room temperature. Poking it, shaking it, or otherwise disturbing it after that causes it to rapidly crystalize. Sodium acetate and water is the only solution I know that does that, but it could also be something else. There's probably source video with more information somewhere.
That actually looks like a liquid nitrogen wand, basically a hollow tube that allows liquid nitrogen through into the water causing a near instant freeze. Just my guess though.
[same guest]
found the source vid
ht tps://www.youtube.com/watch?v=BLq5NibwV5g (FS doesn't like my links, so erase the space in "ht tps")
It's a supersaturated solution of sodium acetate, and a single solid crystal of sodium acetate on the end of the rod to act as a "seed" crystal (like a starting point)
found the source vid
ht tps://www.youtube.com/watch?v=BLq5NibwV5g (FS doesn't like my links, so erase the space in "ht tps")
It's a supersaturated solution of sodium acetate, and a single solid crystal of sodium acetate on the end of the rod to act as a "seed" crystal (like a starting point)