Reaction scheme

[reising1]

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Here's a reaction scheme that we are given. I will use * to indicate radicals

* = radical

Step 1: F3CCl --> F3C* + Cl*
Step 2: Cl* + O3 --> ClO* + O2
Step 3: ClO* + O --> Cl* + O2

Question:
What can be determined about the relative concentrations of F3CCl and O2
A. One equivalent of F3CCl is required to produce one equivalent of O2
B. One equivalent of F3CCl is required to produce two equivalents of O2
C. A catalytic amount of F3CCl can produce much O2
D. The F3CCl is produced by a catalytic amount of O2
Answer: C

I knew the answer would be between B and C, but I don't see why one is better than the other. You can see clearly that 1 F3CCl produces 2 O2. But you can also see clearly that F3CCl can be used as a catalyst and be used over and over. But, they didn't necessarily tell us that the reaction conditions permit the catalyst to be reused, for example. So I was torn and chose the conservative choice, B.

 

[Eastfolding]

You might be overthinking it, but I see where you are coming from. F3CCl is not a catalyst, it breaks down to provide the real catalyst, Cl*.

So I believe the book is correct to say that a catalytic amount of F3CCl can be broken down to produce much O2.

 

[Jepstein30]

Here's a reaction scheme that we are given. I will use * to indicate radicals

* = radical

Step 1: F3CCl --> F3C* + Cl*
Step 2: Cl* + O3 --> ClO* + O2
Step 3: ClO* + O --> Cl* + O2

Question:
What can be determined about the relative concentrations of F3CCl and O2
A. One equivalent of F3CCl is required to produce one equivalent of O2
B. One equivalent of F3CCl is required to produce two equivalents of O2
C. A catalytic amount of F3CCl can produce much O2
D. The F3CCl is produced by a catalytic amount of O2
Answer: C

I knew the answer would be between B and C, but I don't see why one is better than the other. You can see clearly that 1 F3CCl produces 2 O2. But you can also see clearly that F3CCl can be used as a catalyst and be used over and over. But, they didn't necessarily tell us that the reaction conditions permit the catalyst to be reused, for example. So I was torn and chose the conservative choice, B.

1 F3CCl would produce 1 equivalent of Cl.. which in turn can produce infinite amounts of O2 since it is re-generated (catalysis).

F3CCl isn't a catalyst.. note how it just says "catalytic amount" as in = very little.