Smelting of iron ore takes place through this reaction:2Fe2O3(s) + 3C(s) → 4Fe(s) + 3CO2(g) ∆Hfo of Fe2O3 and CO2 are - 8242 kJ mole-1 and -393.7 kJ mole-1 respectively. The reaction is:
Correct answer: A. endothermic
- A. endothermic
- B. exothermic
- C. ∆H = 0
- D. none of the above
Explanation
∆H = (∆Hf°)Products - (∆Hf°)Reactants = 3 × (- 393.7) - 2 × (-824.2) = 476.3 kJ/mole (remember the formula for further use)
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About Enthalpy
Enthalpy is the heat content of a system measured at constant pressure, and its change indicates whether a reaction or physical process is endothermic or exothermic. The topic covers state functions, enthalpy diagrams, standard enthalpy of formation, combustion and neutralisation, and the relationship between ΔH and internal energy change.
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