Thread: Aluminothermic Reactions

Reading up a bit on the fantastic pyrotechnic reaction, I'm terribly curious, how do you calculate the amount of energy produced by the reaction, given different compositions?

Originally Posted by wiki

Thermites can be a diverse class of compositions. The fuels are often aluminium, magnesium, calcium, titanium, zinc, silicon, and boron. The oxidizers can be boron(III) oxide, silicon(IV) oxide, chromium(III) oxide, manganese(IV) oxide, iron(III) oxide, iron(II,III) oxide, copper(II) oxide, and lead(II,III,IV) oxide.[1]

The fact that there are multiple fuel-oxidizer combinations has given me a lot to be curious about, and it made me wonder how you would go about figuring out how much energy is produced from, say, silicon and iron(II,III) oxide.

You should be able to figure it out easily by looking at the standard enthalpies of formation for the metal oxide and silicon (or whatever). I would try googling for "stand enthalpy of formation tables" or something similar. Just subtract the standard enthalpy of formation of the products from that of the reactant, and you get the energy released.