Find incorrect statement w.r.t. catalytic converter

Options

A. Platinum-palladium and rhodium as catalysts
B. Lead in petrol activates the catalysts
C. Reduced the emission of poisonous gases
D. CO and `NO_(x)` changed to `CO_(2)` and `N_(2)` gas

Answer

To find the incorrect statement with respect to catalytic converters, 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 vehicles to reduce harmful emissions. It converts harmful gases produced during combustion into less harmful substances.

2. **Identify the Catalysts Used**:
- The main catalysts used in catalytic converters are platinum, palladium, and rhodium. These metals facilitate the chemical reactions that convert harmful gases into less harmful ones.

3. **Analyze the Options**:
- **Option 1**: "Platinum, palladium, and rhodium as catalysts."
- This statement is correct because these metals are indeed used as catalysts in catalytic converters.
- **Option 2**: "Lead in the petrol activates the catalyst."
- This statement is incorrect. Lead in petrol actually inactivates the catalyst, preventing the catalytic converter from functioning properly.
- **Option 3**: "Reduces the emission of poisonous gases."
- This statement is correct because catalytic converters are designed to reduce emissions of harmful gases like carbon monoxide (CO) and nitrogen oxides (NOx).
- **Option 4**: "CO and NO2 change into carbon dioxide and nitrogen gases."
- This statement is also correct as the catalytic converter helps convert CO and NOx into less harmful gases like CO2 and N2.

4. **Conclusion**:
- The incorrect statement is **Option 2**: "Lead in the petrol activates the catalyst." This is false because lead actually inactivates the catalyst.

### Final Answer:
The incorrect statement regarding catalytic converters is **Option 2**: "Lead in the petrol activates the catalyst."

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