Final Answer:
The reaction between hydrogen peroxide (H₂O₂) and potassium iodide (KI) is exergonic, but the rate of the reaction may still be slow due to other factors such as low concentrations or the need for a catalyst.
Explanation:
While an exergonic reaction releases energy, it does not necessarily mean that the reaction will occur rapidly. Other factors such as concentration and the presence of a catalyst can greatly influence the rate of a reaction. In the case of the reaction between hydrogen peroxide (H₂O₂) and potassium iodide (KI), this reaction is exergonic, meaning it releases energy. However, this reaction may still occur slowly due to low concentrations or the need for a catalyst.
At low concentrations, even if a reaction is exergonic, it may not proceed quickly enough to be observed. This is because at low concentrations, there are fewer reactant molecules available to collide and form products. As a result, the rate of the reaction is slower, and it may take a long time for significant amounts of product to form.
In addition to concentration, the presence of a catalyst can also affect the rate of a reaction. A catalyst is a substance that increases the rate of a reaction without being consumed in the process. In the case of the H₂O₂-KI reaction, iodide ions (I-) can act as a catalyst by facilitating the breakdown of H₂O₂ into water (H₂O) and oxygen (O₂). Without this catalyst, the reaction may proceed much more slowly.
In summary, while an exergonic reaction releases energy, it does not necessarily mean that it will occur rapidly. Factors such as concentration and the presence of a catalyst can greatly influence the rate of a reaction, even for exergonic reactions like H₂O₂-KI.