I need to do a chemistry project and I'm going to do a simple KNO3+ Sucrose smoke mix. I also need to show a chemical equation. I know that the left side of the equation would be: KNO3 + C12H22O11 --heat--> But since I'm not all that experienced with chemistry, I'm not 100% sure on what this smoke mix would yield. I tried googling it, but all I get is how to make a smoke bomb, which I already have instructions for. Thanks. PS: If this belongs in Lab tips or another forum, please move it accordingly.

The exact ammount of specific products depend on more than just the ratio of KNO3 to sucrose. IE at higher pressure on product is more likely to form than another... or at high temperature, etc...

All you can really do is have the breakdown products of sucrose, IE CO2, H2O, C, and have the decomposition products of KNO3, IE K2CO3, possibily KOH, etc... you can't get anything exact without analysing the reaction products, including the gases produced.

Find google groups and search the rec.pyrotechnics group... they have many many years worth of archived searchable threads... you should be able to find some approximations there.

Actually that breakdown is most likely what I need... the class I'm taking isn't any sort of hard class or college level, it's just an ordinary chem class, so the teacher isn't expecting a whole lot.

From what I've heard, it's pretty much impossible to say exactly. Because so there are so many variables (surface area, how fine the granules are, how well it's mixed, what exact type of charcoal you're using), it's nearly random. You can list all the things it COULD form, but not exactly how much of each it will.

Well a generalized statement would be fine. All I need is an ideal equation for the 'perfect' experiment. Something like:

2 KClO3(s)-->2 KCl (s) + 3 O2 (g)

Thing is, you guys are thinking too high fo what I need. I understand where you guys are coming from, but we just need to dumb it down a notch because Honors Chemistry is pretty dumb :-P Thanks for the help though.

Now, if it is in fact impossible to come up with an ideal equation, then I'll concede. But I'm pretty sure there's some sort of equation that we could use for this KNO3+C12H22O11 --heat--> ____.

I'm fairly certain that oxidation will take place. If that occurs, then I think H2O and CO2 will be produced...at least, that's what happened with two other projects that involved burning something.

Well.. I wrote a lengthy responce to how i got to this, but ill cut it back to the bare min... as totse was down for a min and it was lost...

8KNO3 + C12H22O11 + 2O2 > 8CO2 + 11H2O + 4N2 + 4K2CO3

The 2O2 on the reactants side is from the ambient air... its assumed:
2KNO3 -> 2K N2 + 3O2
The O2 goes to oxidizing the C in sucrose...
The 2K reacts with ambient oxygen from the air forming K2O which reacts with some of the CO2 from the sucrose forming K2CO3... However this is flawed as no K actually forms... KNO3 decomposes to KNO2, then with loss of NO forming K2O or something like that... so yeah not actually what happens.. but the teacher might believe it... or you can just say this is sorta what could happen... and this reaction is way to complex.

Also, don't forget that it IS an exothermic reaction, so the heat is a product instead of a reactant. You probably put it on the left because you know you have to light a fuse to get it started, well, that's the initiation energy. Obviously, a lot more energy than that is released from the compound as it decomposes. So, it should look something like:

(a)KNO3 + (b)C12H22O11 ---> (c)CO2 + (d)H2O + (e)K2CO3 + (f)CO + (g)N2 ...et + Heat (delta H)

(where a-g are coefficients)