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Years ago, I watched a Johnny Carson episode where a guest on the show mixed a compound with ordinary table sugar and added a drop of water and the mixture burst into flames. I went and bought the stuff at a chemical supply and we had a lot of fun with it. Over the years I have tried to remember what the compound was. I think it was a sodium or potassium compound with a trioxide $\ce{O3}$ at the end but not sure about that. We would mix the compound $50-50$ with sugar and adding 1 drop of water caused a reaction that flamed up pretty good. Does anyone know this trick? I would love to try this again.

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    $\begingroup$ You can mix sugar with potassium chlorate ($\ce{KClO3}$) and then pour a few drops of sulfuric acid on it to create a fire: angelo.edu/faculty/kboudrea/demos/instant_fire/instant_fire.htm . This is a very violent and unsafe reaction though. $\endgroup$
    – S R Maiti
    Commented Jun 22, 2021 at 7:57
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    $\begingroup$ @ShoubhikRMaiti I remember using these mixtures with metal salts as "bengal fire" effects, when I assisted my professor to prepare effects for TV, when I was studing at a chemical high school in early 80s. Not sure about mixtures with just water drops. It is applicable for iodine + aluminium dust, but it produces iodine vapours, not flame. Perhaps mixture sugar + KClO3 + solid organic acid ? But it would be unsafe to keep. $\endgroup$
    – Poutnik
    Commented Jun 22, 2021 at 8:35
  • $\begingroup$ @Poutnik The website says sulfuric acid is a catalyst. My guess is that sulfuric acid would carbonify some of the sugar, which would then be oxidised by KClO3. In that case, would an organic acid work? I am not really sure though. The iodine and aluminium idea seems more promising, this video shows that a flame can be seen in that reaction: youtube.com/watch?v=RclM2S2YIBg $\endgroup$
    – S R Maiti
    Commented Jun 22, 2021 at 11:46
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    $\begingroup$ @ShoubhikRMaiti Hm, I would rather say $\ce{H2SO4}$ partially converts $\ce{KClO3}$ to much more reactive $\ce{HClO3}$. Even $\ce{HClO4}$, which is less reactive than $\ce{HClO3}$, ignites organic matter. // I2 + Al, the amount of mixture of water temperature may matter. $\endgroup$
    – Poutnik
    Commented Jun 22, 2021 at 11:51
  • $\begingroup$ No, this was a simple mixture of sugar and the granules and 1 drop of water would set it off. No acids or anything like that. The one time we put in a pvc pipe, it nearly blew the guy's hand off. I've seen sugar rocket engines on YouTube - it is similar to that type of reaction. I made this post almost 3 years ago and was googling and came across it. $\endgroup$
    – user142982
    Commented Jan 26 at 4:27

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It is probably a mixture of sodium chlorite $\ce{NaClO2}$ and ammonium thiocyanate $\ce{NH4SCN}$. It takes fire with the least drop of water. But the mixture is difficult to do, because these two products have to be totally dry, and ammonium thiocyanate is rather hygroscopic. If they are even a bit wet, they react and take flame by simple contact. It is even safer not to try to mix the products. Just add some sodium chlorite to a pile of ammonium thiocyanate in a crucible, without touching anything. And add one drop of water. The fire lasts one or two seconds, producing some $\ce{NaCl}$ smoke and leaves a yellow deposit of sulfur. Mind ! Don't confuse sodium chlorite $\ce{NaClO2}$, with sodium chlorate $\ce{NaClO3}$, which is more common. The reaction is :$$\ce{2NaClO2 + NH4SCN -> 2NaCl + S + 2 H2O + N2 + CO2}$$ If you add some more sodium chlorite to the hot mixture, the sulfur will burn according to : $$\ce{S + NaClO2 -> SO2 + NaCl}$$

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