chemistry question, reactivity stuff.. maybe..

[FadeToBlackened]

Ok.

Some oxidizers release oxygen easier than others, and some fuels burn hotter than others, right? Where are the numbers? I mean, nitrates are a lot easier to use than sulfates as oxidizers, but why is this, and where may I learn more about it?

We all know magnesium burns hot, thermite hotter, while KNO3 + charcoal, not as hot. I've also heard KMnO4 + Fe goes pretty hot. What is the idea behind why this happens?

[Anthony]

Heat of decompostion - the amount of chemical energy required to make an oxidiser release its oxygen:

KClO4: -0.68
NH4ClO4: -108.3
KNO3: 75.5
Sr(NO3)2: 92
Ba(NO3)2: 104
KClO3: -10.6
Ba(ClO3)2: -28

A negative number means that the compound gives off heat energy whilst decomposing. Compounds with large negative figures (like NH4ClO4) mean that they can, under certain conditions, self-oxidise.

Heat of combustion for various fuels (Kcal/gram):

boron: 14
napthalene: 9.6
stearic acid: 9.5
carbon: 7.8
aluminium: 7.4
silicon: 7.4
hexamine: 7.2
magnessium: 5.9
phosphorus: 5.9
titanium: 4.7
PVC: 4.4
dextrin: 4.2
red gum: 4
sucrose, lactose: 3.9
glucose: 3.7
zirconium: 2.9
sulphur: 2.2
iron: 1.8
zinc: 1.3
parlon: ~0

[Volcano]

It's all down to the molecular structure of the compounds. Without going into the realms of quantum chemistry, exothermic (heat releasing) reactions release the stored energy within the compound itself.
KNO3+S+C react to give SO2, CO3 etc and these products of the reaction have a lower internal energy level than the original reactants themselves. The difference in energy is emitted as the explosion you see and hear.

You can get a big book on chemistry or maybe learn part-time at college etc. What you are interested in is called Thermodynamics.

[vulture]

Redox potential indicates the strenght of oxidizers and reducers in solution and usually this can be used for dry comparison with a few exceptions.
Please don't make the mistake that the more oxygen atoms, the more powerful the oxidizer is.

[simply RED]

What is delta Q of the equilibrium
NH4NO3 = N2 + 2H2O + 1/2O2

[vulture]

At which temperature?
I don't have any exact figures but this reaction will go to the right above the melting point obviously.