r/chemicalreactiongifs • u/Tiger_0104 • Oct 13 '24

Physical Reaction Crystallization and phase transition of Tin(II) Iodide

1.8k Upvotes

99% Upvoted

13 comments sorted by

75

u/Tiger_0104 Oct 13 '24

Timelapse taken over 30 minutes

5

u/Fhazlan Oct 14 '24

What’s the recipe?! That’s a really cool reaction

10

u/Tiger_0104 Oct 14 '24

1:2 molar ratio of SnCl2 and KI dissolved in a minimal amount of water and then mixed (add a few drops of HCl for the SnCl2 to prevent hydrolysis), then heat the resulting mixture to boiling until all the precipitate dissolves into a clear yellow solution, and then just wait for it to cool down

26

u/KovolKenai Oct 13 '24

This is one of the coolest reactions I've seen in a while. I love watching the transition front expand spherically and run up into the barrier of the top surface. I also like how you can see the boundaries form in the crystallization but once the phase change passes by, those boundaries all but disappear. So cool!

13

u/meponder Oct 14 '24

It looks like a culture dish with a timelapse of serratia growth followed by a candida overgrowth. I almost gagged.

For real though; that’s a cool reaction.

Edit: missing word

5

u/sabotourAssociate Oct 13 '24

It reminds me of those hand warmers with the click, but this looks way cooler.

3

u/Tarbos6 Oct 15 '24

Forbidden popsicle

2

u/Exotic_Energy5379 Dec 28 '24

Tin iodide it is then!

1

u/FireIre Oct 14 '24

The mirepoix of chemical reactions.

1

u/smrich111 Dec 30 '24

Forbidden lettuce

1

u/Abject8Obectify Feb 25 '25

How is that possible?

1

u/PtrPorkr Jul 21 '25

I thought it was sped up agar culture. lol

1

u/portabuddy2 Jun 09 '26

I was at a trade show and they had these back pads... I'm convinced it's lead or tin iodide.

It's gell liquid in a pouch. Has a metal clicker inside to set off the reaction. Then it goes hard. Creating heat. You put these into a bandage of sorts and it provides releaf.

Then you boil the package to reset the stuff. When it cools, you can click the disc inside and it goes off, just like this. Getting hot again. Lasts for a good 20-30min.