last one :
Using the table below, what is the change in enthalpy for the following reaction?
3CO (g) + 2Fe2O3 (s) Fe(s) + 3CO2 (g)

Substance ΔHf (kJ/mol)
CO2 (g) -393.5
CO (g) -110.5
O2 (g) 0.0
O3 (g) 142.0
Fe2O3 (s) -822.1
Fe(s) 0.0 0.0

Question

last one :
Using the table below, what is the change in enthalpy for the following reaction?
3CO (g) + 2Fe2O3 (s)  Fe(s) + 3CO2 (g)


Substance	ΔHf (kJ/mol)
CO2 (g)	       -393.5
CO (g)	         -110.5
O2 (g)	           0.0
O3 (g)	         142.0
Fe2O3 (s) 	-822.1
Fe(s)	0.0             0.0

jfraser · Answer

same way, add up all the DH of all the products, then subtract the DH of all the reactants. You have to multiply by the stoich coefficient. If you make 3 mols of CO2, you have to multiply the -393.5kJ by 3

jfraser · Answer

$$[3(-393.5kJ)] - [3(-110.5kJ) + 2(-822.1kJ)]$$
I get 795.2kJ

anonymous · Answer

i got the same result as well.