Questions: Question 2 1 pts Mexican chemist Mario J. Molina was one of three chemists who received the Nobel Prize in chemistry in 1995 for his work in determining that chloroflourocarbons (CFCs) release Cl atoms into the atmosphere, leading to the depletion of the ozone layer. The two-step mechanism for the resulting reaction is shown below. step 1 Cl+O3 -> ClO+O2 step 2 ClO+O -> Cl+O2 Why does a small amount of CFCs lead to a large loss of ozone? (There may be more than one answer. Select all that apply.) Since it is a catalyst, it must absorb UV radiation from sunlight before it can be active. As a catalyst, it is created in the reaction mixture before it changes the rate of the reaction As a catalyst, it can speed up many cycles of the same reaction Because it is a catalyst, it causes the reaction to occur faster but isn't consumed during the reaction. Since it is a catalyst, it stabilizes the products of the reaction

Solution Steps

A catalyst is a substance that increases the rate of a chemical reaction without being consumed in the process. It can participate in multiple reaction cycles, thereby significantly increasing the overall reaction rate.

The given two-step mechanism involves chlorine (Cl) acting as a catalyst:

1. \(\mathrm{Cl} + \mathrm{O}_3 \rightarrow \mathrm{ClO} + \mathrm{O}_2\)
2. \(\mathrm{ClO} + \mathrm{O} \rightarrow \mathrm{Cl} + \mathrm{O}_2\)

In this mechanism, Cl is regenerated in the second step, allowing it to participate in multiple cycles of the reaction.

• Option 1: "Since it is a catalyst, it must absorb UV radiation from sunlight before it can be active." This is not necessarily true for all catalysts and is not relevant to the given reaction mechanism.
• Option 2: "As a catalyst, it is created in the reaction mixture before it changes the rate of the reaction." This is incorrect because the catalyst (Cl) is not created in the reaction mixture; it is introduced by the breakdown of CFCs.
• Option 3: "As a catalyst, it can speed up many cycles of the same reaction." This is correct because Cl can participate in multiple cycles of the reaction, leading to a large loss of ozone.
• Option 4: "Because it is a catalyst, it causes the reaction to occur faster but isn't consumed during the reaction." This is correct because Cl is regenerated and not consumed in the overall reaction.
• Option 5: "Since it is a catalyst, it stabilizes the products of the reaction." This is incorrect because the role of a catalyst is to speed up the reaction, not to stabilize the products.

Final Answer