Honors Chemistry Name______________________________

Hess' Law PMP

Brooks/McAfoos Period_________ Date_________________

 

Determine the ΔHrxn for the reaction N2 (g) + 5/2 O2 (g) N2O5 (g) from the following:

 

2 H2 (g) + O2 (g) 2 H2O (l)

 

 

-136.6 kcal

N2O5 (g) + H2O (l) 2 HNO3 (l)

 

 

-18.3 kcal

1/2 N2 (g) + 3/2 O2 (g) + 1/2 H2 (g) HNO3 (l)

-41.6 kcal

 

 

 

Determine the ΔHrxn for the reaction B2H6 (g) + 6 Cl2 (g) 2 BCl3 (g) + 6 HCl (g) from the following:

 

BCl3 (g) + 3 H2O (l) H3BO3 (s) + 3 HCl (g)

 

 

-112.5 kJ

B2H6 (g) + 6 H2O (l) 2 H3BO3 (s) + 6 H2 (g)

 

 

-493.4 kJ

1/2 H2 (g) + 1/2 Cl2 (g) HCl (g)

-92.3 kJ

 

 

 

Determine the ΔHrxn for the reaction N2H4 (g) + O2 (g) N2 (g) + 2 H2O (g) from the following:

 

H2 (g) + O2 (g) H2O (g)

 

-286 kJ

2 NH3 (g) + O2 (g) N2H4 (g) + H2O (g)

 

-143 kJ

N2O (g) + 3 H2 (g) N2H4 (g) + H2O (g)

 

-317 kJ

2 NH3 (g) + 3 N2O (g) 4 N2 (g) + 3 H2O (g)

-1010 kJ

 

 

 

Determine the ΔHrxn for the reaction C (s) + 2 H2 (g) CH4 (g) from the following:

 

C (s) + O2 (g) CO2 (g)

 

-394 kJ

H2 (g) + O2 (g) H2O (g)

 

-286 kJ

CH4 (g) + 2 O2 (g) CO2 (g) + 2 H2O (g)

-890 kJ

 

 

 


Determine the ΔHrxn for the reaction N2 (g) + O2 (g) N2O (g) from the following:

 

2 NH3 (g) + 3 N2O (g) 4 N2 (g) + 3 H2O (g)

 

-1010 kJ

4 NH3 (g) + 3 O2 (g) 2 N2 (g) + 6 H2O (g)

-1531 kJ

 

 

 

Determine the ΔHrxn for the reaction 2 S (s) + 2 OF2 (g) SO2 (g) + SF4 (g) from the following:

 

OF2 (g) + H2O (g) O2 (g) + 2 HF (g)

 

-277 kJ

SF4 (g) + 2 H2O (g) SO2 (g) + 4 HF (g)

 

-828 kJ

S (s) + O2 (g) SO2 (g)

-297 kJ

 

 

 

Determine the ΔHrxn for the reaction 3 Fe (s) + 4 H2O (l) Fe3O4 (s) + 4 H2 (g) from the following:

 

FeO (s) + H2 (g) Fe (s) + H2O (l)

 

25.0 kJ

3 FeO (s) + O2 (g) Fe3O4 (s)

 

-318 kJ

H2 (g) + O2 (g) H2O (l)

-242 kJ

 

 

 

Determine the ΔHrxn for the reaction Fe2O3 (s) + 3 CO (g) 2 Fe (s) + 3 CO2 (g) from the following:

 

3 Fe2O3 (s) + CO (g) 2 Fe3O4 (s) + CO2 (g)

 

-46 kJ

FeO (s) + CO (g) Fe (s) + CO2 (g)

 

9.0 kJ

Fe3O4 (s) + CO (g) 3 FeO (s) + CO2 (g)

-41 kJ