Catalytic converters use expensive metals as catalysts.
What precaution should be observed while using catalytic converter ?

Explanation

### Step-by-Step Solution:

1. **Understanding Catalytic Converters**:
- A catalytic converter is an essential component in vehicles that helps reduce harmful emissions. It contains catalysts, typically made from expensive metals like platinum, palladium, and rhodium, which facilitate chemical reactions to convert toxic gases into less harmful substances.

2. **Function of Catalysts**:
- Catalysts are substances that speed up chemical reactions without being consumed in the process. In the case of catalytic converters, they help in converting carbon monoxide (CO), hydrocarbons (HC), and nitrogen oxides (NOx) into carbon dioxide (CO2), nitrogen (N2), and water (H2O).

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