which of the following statements is true?\nthe overall chemical reaction is exothermic.\nthere are two…

which of the following statements is true?\nthe overall chemical reaction is exothermic.\nthere are two intermediate reactions in this system.\nthe third intermediate reaction is endothermic.\nthe longest arrow represents the overall chemical reaction.

which of the following statements is true?\nthe overall chemical reaction is exothermic.\nthere are two intermediate reactions in this system.\nthe third intermediate reaction is endothermic.\nthe longest arrow represents the overall chemical reaction.

Answer

Explanation:

Step1: Analyze exothermic/endothermic

Since $\Delta H_{rxn}$ is downward - pointing (negative), heat is released. So the overall reaction is exothermic.

Step2: Analyze intermediate reactions

There are 3 arrows ($\Delta H_1$, $\Delta H_2$, $\Delta H_3$) representing steps, but we can't say there are two intermediate reactions just from this.

Step3: Analyze third - step endothermicity

$\Delta H_3$ is downward - pointing (negative), so the third step is exothermic, not endothermic.

Step4: Analyze longest arrow

The longest arrow doesn't necessarily represent the overall reaction.

Answer:

The overall chemical reaction is exothermic.