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Average Bond Energies and Delta H.

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My text gives the example of the following reaction:

H2(g) + Cl2(g)-->2HCl(g) / 2 moles HCl

To break bond
1 mole H-H bonds x 432 kJ/mol = 432 kJ
1 mole Cl-Cl bonds x 240 kJ/mole = 240 kJ
432 + 240 = 672 kJ

Energy released / bond making
2 mol H-CL bonds x 428 = 856 kJ

bond breaking +672
bond making -856
net change = -184 KJ/2 moles of HFL = 92 kJ/mol HCL = exothermic

I understand this when it is 1:1 (H-H), but how is a problem such as:
H-S-H + Cl-Cl --> Cl-S-Cl + H-H approached?

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Solution Summary

Stepwise solution to find heat of reaction using bond energy values.

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H-S-H + Cl-Cl --> Cl-S-Cl + H-H

For such type of problem, you need to look into how many individual bond as well as type of bonds ...

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