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title: "The destruction of ozone in the upper atmosphere by atomic chlorine is proposed to proceed by the following two-step gas-phase mechanism:  \\[ \\text{Step 1: } \\text{Cl(g)} + \\text{O}_3\\text{(g)} \\rightarrow \\text{ClO(g)} + \\text{O}_2\\text{(g)} \\] \\[ \\text{Step 2: } \\text{ClO(g)} + \\text{O(g)} \\rightarrow \\text{Cl(g)} + \\text{O}_2\\text{(g)} \\]  Which of the following correctly identifies the role of \\(\\text{Cl(g)}\\) and the role of \\(\\text{ClO(g)}\\) in this reaction mechanism?"
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url: "https://nerd-notes.com/ubq/119658/"
date_modified: "2026-08-21T08:11:57+00:00"
---

# The destruction of ozone in the upper atmosphere by atomic chlorine is proposed to proceed by the following two-step gas-phase mechanism:

\[ \text{Step 1: } \text{Cl(g)} + \text{O}_3\text{(g)} \rightarrow \text{ClO(g)} + \text{O}_2\text{(g)} \]
\[ \text{Step 2: } \text{ClO(g)} + \text{O(g)} \rightarrow \text{Cl(g)} + \text{O}_2\text{(g)} \]

Which of the following correctly identifies the role of \(\text{Cl(g)}\) and the role of \(\text{ClO(g)}\) in this reaction mechanism?

The destruction of ozone in the upper atmosphere by atomic chlorine is proposed to proceed by the following two-step gas-phase mechanism:

\[ \text{Step 1: } \text{Cl(g)} + \text{O}_3\text{(g)} \rightarrow \text{ClO(g)} + \text{O}_2\text{(g)} \]
\[ \text{Step 2: } \text{ClO(g)} + \text{O(g)} \rightarrow \text{Cl(g)} + \text{O}_2\text{(g)} \]

Which of the following correctly identifies the role of \(\text{Cl(g)}\) and the role of \(\text{ClO(g)}\) in this reaction mechanism?

- **A.** \(\text{Cl(g)}\) is a reaction intermediate, and \(\text{ClO(g)}\) is a catalyst.
- **B.** \(\text{Cl(g)}\) is a reaction intermediate, and \(\text{ClO(g)}\) is an overall product.
- **C.** \(\text{Cl(g)}\) is a catalyst, and \(\text{ClO(g)}\) is a reaction intermediate.
- **D.** \(\text{Cl(g)}\) is a catalyst, and \(\text{ClO(g)}\) is an overall reactant.

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/119658/*