Understanding Enthalpy of Reaction in the Thermite Reaction

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The thermite reaction between Fe2O3 and Al is highly exothermic, producing molten iron rapidly. To calculate the heat liberated, Hess's law can be applied to determine the enthalpy changes for the reaction involving one mole of Fe2O3 with aluminum. The correct balanced equation for the reaction is Fe2O3 + 2Al → Al2O3 + 2Fe. It's important to denote the states of the reactants and products and consider the stoichiometry when calculating the enthalpy values. The discussion emphasizes the need to carefully analyze the enthalpy terms and the proper reaction equation for accurate calculations.
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I've been having trouble understanding some parts of these questions. The question goes like this:

The "thermite reaction" is highly exothermic. It involves the reaction between Fe2O3 & Al. The reaction produces white-hot, molten iron is a few seconds.
2 Al + 3/2 O2 --> Al2O3 delta H = -1672 kJ
2 Fe + 3/2 O2 --> Fe2O3 delta H = -836 kJ​

a) find the amount of heat liberated in the reaction of one mole of Fe2O3 with Al.
b) find the amount of heat liberated in the reactino of 1 kg of Fe2O3 with Al.
c) how many grams of liquid water could be heated from 0C to 100C by the heat liberated per mole of aluminum oxide?

For a) and b), when I'm trying to find the enthalpy, do I need to apply hess's law to obtain the enthalpy of one mole of Fe2O3 and Al? The part that confuses me is the relevance with Fe2O3 and Al. So far, I've only gotten to figuring out what the target eq'n is.

2 Al + 2 Fe --> Al2O3 + Fe203 delta H = -836kJ​

But after determining the target eq'n, I don't know what to do in terms of Fe2O3 and Al for that one mol and similarly with determining 1 kg.
 
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If they want the reaction of the iron oxide with aluminum (you should denote the states of the molecules/atoms involved), your final equation is incorrect. Write the proper equation, and observe on whether the terms in the enthalpy values for each denoted reaction (kJ/mol, kJ/grams or kJ/mol reaction, kJ/mol Al etc...), the rest should be simple, Don't forget to take into account the stoichiometries.
 
So really, it's just a single displacement rxn then between Al and Fe2O3?
 
yes, Fe2O3 + 2Al → Al2O3 + 2Fe, I'm sure you can take it from here
 
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