Platinum is used as a catalyst.

Explanation

**Step-by-Step Solution:**

1. **Understanding the Statement**: The statement we need to evaluate is "Platinum is used as a catalyst."

2. **Definition of a Catalyst**: A catalyst is a substance that increases the rate of a chemical reaction without undergoing any permanent change itself.

3. **Role of Platinum**: Platinum is known for its catalytic properties, particularly in reactions that occur in the gaseous state.

4. **Mechanism of Action**: Platinum acts by collecting oxygen atoms. It facilitates the oxidation of substances, such as carbon monoxide (CO).

5. **Conversion Process**: When platinum collects oxygen, it helps convert carbon monoxide (CO) into carbon dioxide (CO2). This conversion is significant because CO is a harmful gas, while CO2 is less harmful.

6. **Conclusion**: Since platinum is indeed used as a catalyst in various chemical reactions, particularly in the oxidation of carbon monoxide, the statement "Platinum is used as a catalyst" is true.

**Final Answer**: True

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