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