The thermite reaction, Fe₂O₃ + Al → Al₂O₃ + Fe produces so much heat that the Fe product melts. This reaction is used industrially to weld metal parts under water, where a torch cannot be employed. It is also a favorite chemical demonstration in the lecture hall (on a small scale).
(a) Balance the chemical equation for the thermite reaction, and include the proper states of matter.
(b) Calculate how many grams of aluminum are needed to completely react with 500.0 g of Fe₂O₃ in this reaction.
(c) This reaction produces 852 kJ of heat per mole of Fe₂O₃ reacted. How many grams of Fe₂O₃ are needed to produce 1.00 x 10⁴ kJ of heat?
(d) If you performed the reverse reaction— aluminum oxide plus iron makes iron oxide plus aluminum—would that reaction have heat as a reactant or a product?