Which metal inactivates a catalytic converter ?

Options

A. Gold
B. Iron
C. Silver
D. Lead

Answer

To answer the question "Which metal inactivates a catalytic converter?" we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Function of a Catalytic Converter**:
- A catalytic converter is a device used in motor vehicles to reduce harmful emissions. It contains catalysts that facilitate chemical reactions to convert toxic substances into less harmful gases.

2. **Identify the Catalysts Used**:
- The primary catalysts used in catalytic converters are precious metals, such as platinum, palladium, and rhodium. These metals help in the conversion of harmful gases like hydrocarbons into less harmful substances.

3. **Recognize the Issue with Certain Metals**:
- Some metals can interfere with the functioning of the catalytic converter. This interference can lead to the inactivation of the catalyst, which is detrimental to the converter's ability to reduce emissions.

4. **Evaluate the Given Options**:
- The options provided are gold, iron, silver, and lead. We need to determine which of these metals can inactivate the catalytic converter.

5. **Focus on Lead**:
- Lead is known to bind to the catalysts in the catalytic converter. When lead is present, it can coat the catalyst, preventing it from functioning effectively. This is why leaded petrol is harmful and is now largely replaced by unleaded petrol.

6. **Conclusion**:
- Based on the information, the metal that inactivates a catalytic converter is **Lead**.

### Final Answer:
Lead inactivates a catalytic converter.

---