Boring chemistry problem

[sevenperforce]

I can balance equations but only if I already know both sides. Trying to find the following products:

Na2S2O5 + O2 = ?

Na2S2O5 + KNO3 = ?

Na2S2O5 + KNO3 + Fe2O3 = ?

Na2S2O5 + KNO3 + C12H22O11 = ?

KNO3 + C12H22O11 = ?

KNO3 + C12H22O11 + Fe2O3 = ?

Thanks!

[UmbralRaptor]

...are you asking us yo do your homework for you?

Edited July 22, 2016 by UmbralRaptor

[qzgy]

This looks like a HW problem. Why not ask the internet first before the forums?

[sevenperforce]

Looks like a homework problem because it's a very specific question, but it isn't actually homework. I graduated college a long time ago. 

Trying to estimate specific impulse of different solid fuels, but I can't get specific impulse without specific energy, and I can't get specific energy unless I know the equation products so I can balance it and calculate bond energies.

[PB666]

Na₂S₂O₅ + O₂  ----> Na₂S0₄ + S0₃

Na₂S₂O₅ + KNO₃  ----> Na₂S0₄ + KNO + S0₃  ----> Na₂S0₄ + 1/2K₂S0₄ + 1/2N₂

Na₂S₂O₅ + 2KNO₃  ----> 2KNaS0₄ + N₂O₃ 

Na₂S₂O₅ + KNO₃  + C₁₂H₂₂O₁₁ =

12C - 12CO₂ Need 24O

22H - 11 H20   Need 11O

11O

The net requirment is 240

8 Na₂S₂O₅ + 16 KNO₃ + C₁₂H₂₂O₁₁ --------> 16 KNaS0₄ + 8 N₂ +  12 CO₂ +  11 H₂0

Of all the reactions this one looks like it has the best thermodynamics, pretty much driven by the potassium nitrate. The reaction will not go to completion and there will be a ton of nitrous oxide byproducts. There is no way to catalyze the reaction to completion because the sulfur has a poisoning effect.

Edited July 22, 2016 by PB666

[sevenperforce]

Thanks!

[KSK]

A couple of those don't look quite right. For the first one, I'm not sure you'd get sulphur trioxide formed preferentially over sulphur dioxide but it's easy to rebalance.

2 Na2S2O5 + 3 O2 = 2 Na2SO4 + 4 SO2

Likewise for the third one, I don't think you'd get N2O3 as a product. My gut feel was that it would probably break down to nitrogen and oxygen and Wikipedia confirms. So...

2 Na2S2O5 +  4 KNO3  ----> 4 KNaS04 +  2 N2 + 3O2

Those are all pretty stable reaction products. Getting oxygen out as a reactant is weird, although you do have a lot of spare oxygen in that system. Maybe you'd get some nitrogen oxides out instead, just not N2O3

For the reactions involving iron oxide, I have no idea what you'd get out. The iron oxide is either going to be inert or acting as a catalyst (hence my uncertainty about reaction products) but you're already at FeIII and potassium nitrate isn't a strong enough oxidiser to move it to FeIV, so the iron oxide isn't going be participating in a net reaction.

 

[QuesoExplosivo]

Why would anyone use sodium metabisulfite as a rocket fuel? It seems like a really bad choice to me.

[PB666]

9 hours ago, KSK said:

A couple of those don't look quite right. For the first one, I'm not sure you'd get sulphur trioxide formed preferentially over sulphur dioxide but it's easy to rebalance.

2 Na2S2O5 + 3 O2 = 2 Na2SO4 + 4 SO2

Likewise for the third one, I don't think you'd get N2O3 as a product. My gut feel was that it would probably break down to nitrogen and oxygen and Wikipedia confirms. So...

2 Na2S2O5 +  4 KNO3  ----> 4 KNaS04 +  2 N2 + 3O2

Those are all pretty stable reaction products. Getting oxygen out as a reactant is weird, although you do have a lot of spare oxygen in that system. Maybe you'd get some nitrogen oxides out instead, just not N2O3

For the reactions involving iron oxide, I have no idea what you'd get out. The iron oxide is either going to be inert or acting as a catalyst (hence my uncertainty about reaction products) but you're already at FeIII and potassium nitrate isn't a strong enough oxidiser to move it to FeIV, so the iron oxide isn't going be participating in a net reaction.

 

IKR, you would use metabisulfite with chlorine not oxygen.