Hey please help me to explain this topic. I only need answer in typed format. DO

Question

Hey please help me to explain this topic. I only need answer in typed format. DOn't post any picture in solution. And be specific and easy to grasp.

Hess' Principle

Use the following information to calculate the heat of formation of propane, C3H8.

                                    3 C (graph) + 4 H2 (g) ® C3H8 (g)

1. C (graph) + O2 (g) ® CO2 (g)       DH = - 393.5 kJ

2. H2 (g) + ½ O2 (g) ® H2O (l)           DH = - 285.8 kJ

3. C3H4 (g) + 4 O2 (g) ® 3 CO2 (g) + 2 H2O (l)     DH = - 1937 kJ

4. C3H6 (g) + 9/2 O2 (g) ® 3 CO2 (g) + 3 H2O (g)   DH = - 2007 kJ

5. C3H8 (g) + 5 O2 (g) ® 3 CO2 (g) + 4 H2O (l)   DH = - 2219.1 kJ

Explanation / Answer

C (graph) + O2 (g) ® CO2 (g)       DH = - 393.5 kJ

3C (graph) + 3O2 (g) ® 3CO2 (g)       DH = - 393.5*3 kJ--------------i

H2 (g) + ½ O2 (g) ® H2O (l)           DH = - 285.8 kJ

4 H2 (g) + 2O2 (g) ® 4H2O (l)           DH = - 285.8*4 kJ-------------ii

adding i+ii

3C (graph) + 3O2 (g) + 4 H2 (g) + 2O2 (g)  ® 3CO2 (g) + 4H2O (l) DH=-393.5*3+(-285.8*4) kJ = -2323.7 kJ ----iii

C3H8 (g) + 5 O2 (g) ® 3 CO2 (g) + 4 H2O (l)   DH = - 2219.1 kJ

3 CO2 (g) + 4 H2O (l) ®   C3H8 (g) + 5 O2 (g)  DH = 2219.1 kJ-----------iv

iv+iii

3 CO2 (g) + 4 H2O (l) + 3C (graph) + 3O2 (g) + 4 H2 (g) + 2O2 (g)  ®   C3H8 (g) + 5 O2 (g) +3CO2 (g) + 4H2O (l)  

DH=2219.1-2323.7= 104.6 kJ

so finally we get the result i.e.

3 C (graph) + 4 H2 (g) ® C3H8 (g)     DH= 104.6 kJ

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