1º BACHILLERATO/QUÍMICA/TERMOQUÍMICA/ENTALPÍAS DE REACCIÓN Tostación de pirita La tostación de la pirita se produce según:

4 FeS2 (s) +11 O2 (g) → 2 Fe2O3 (s) + 8 SO2 (g)

Calcule la cantidad de calor, en KJ, a presión constante, desprendida en la combustión de #mpi g de pirita del #riq % de riqueza en peso.

Datos: Masas atómicas: Fe = 55’8; S = 32. ΔHºf[FeS2(s)] = −177’5 kJ/mol, ΔHºf[Fe2O3(s)] = −822’2 kJ/mol, ΔHºf[SO2(g)]= −296’8 kJ/mol.

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