Answer:
-1043,8 KJ
Step-by-step explanation:
Hello!
It is necessary to accommodate the reactions to get the reaction of my interest.
Reaction A reverses what modifies its energy in its sign (+72.6 KJ).
Reaction B doubles, which also doubles its energy (-514.4 KJ x 2).
Reaction C reverses what modifies its energy in its sign (-87.6 KJ).
By sum of the energies I get the energy of the global reaction.
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