London smog is __________ in nature whereas photochemical smog is ______in nature.

Answer

To solve the question, we need to identify the nature of London smog and photochemical smog.

1. **Understanding London Smog**:
- London smog, also known as classical smog, occurs primarily during the winter season.
- It is characterized by the presence of pollutants such as sulfur dioxide (SO2) and particulate matter.
- The nature of London smog is **reducing** because it contains reducing agents like sulfur dioxide.

2. **Understanding Photochemical Smog**:
- Photochemical smog occurs during the summer season, typically on hot, sunny days.
- It is formed through the reaction of sunlight with nitrogen oxides and volatile organic compounds (VOCs), leading to the formation of secondary pollutants like ozone.
- The nature of photochemical smog is **oxidizing** because it involves the formation of oxidizing agents like ozone.

3. **Filling in the Blanks**:
- Therefore, we can fill in the blanks in the question:
- London smog is **reducing** in nature whereas photochemical smog is **oxidizing** in nature.

Final Answer: London smog is **reducing** in nature whereas photochemical smog is **oxidizing** in nature.

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