This graph shows the energy changes during the progress of a reaction involving two molecules. Explain what is happening or what the state of the reaction is at A, B, C, and D. Is this an exothermic o

This graph shows the energy changes during the progress of a reaction involving two molecules. Explain what is happening or what the state of the reaction is at A, B, C, and D. Is this an exothermic or an endothermic reaction?

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