Given: Fe2O3(s) + 3 CO(g) –––––> 2 Fe(s) + 3 CO2(g); ΔH° = –26.8 kJ FeO(s) + CO(g) –––––> Fe(s) + CO2(g); ΔH° = –16.5 kJ determine ΔH° for the following thermochemical equation. Fe2O3(s) + CO(g) –––––> 2 FeO(s) + CO2(g)

ΔH° = + 6.2 kJ

Explanation:

Fe₂O₃(s) + 3CO(g) –––––> 2 Fe(s) + 3 CO₂(g);        ΔH° = –26.8 kJ   ( 1 )

  FeO(s) + CO(g) –––––> Fe(s) + CO₂(g);                  ΔH° = –16.5 kJ  ( 2 )

   Multiplying equation ( 2 ) by 2 and subtracting it from ( 1 )

  Fe₂O₃(s) + 3CO(g) -2 FeO(s) -  2CO(g) ––> 2 Fe(s) + 3 CO₂(g) - 2Fe(s) -           2CO₂(g)              ΔH° = –26.8 kJ  -  ( 2 x –16.5 kJ )

Fe₂O₃(s) + CO(g) -2 FeO(s)––>  CO₂(g)              ΔH° = –26.8 kJ + 33 kJ

Fe₂O₃(s) + CO(g) ––>2 FeO(s) +CO₂(g)               ΔH° = + 6.2 kJ

Required   ΔH° = + 6.2 kJ       Ans .

i do not get it   at all