We are asked to calculate how much heat (in kilojoules) a hand warmer containing 21.0 g of iron powder produces.
Note that we need to multiply each ΔH˚f by the stoichiometric coefficient since ΔH˚f is in kJ/mol.
Also, note that ΔH˚f for elements in their standard state is 0.
ΔH°rxn = 1648.4 kJ
Dry chemical hand warmers utilize the oxidation of iron to form iron oxide according to the following reaction:
4 Fe(s) + 3O2(g) → 2Fe2O3(s)
Standard thermodynamic quantities for selected substances at 25 o m C
|Reactant or product||ΔH°f (kJ/mol)|
Calculate how much heat (in kilojoules) a hand warmer containing 21.0 g of iron powder produces.
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