Q. In a photochemical smog, which gas causes irritation to mucous membrane and respiratory system?
Answer: Ozone
Notes: Ozone (O3) is the most common photochemical oxidant in photochemical smog. Inhaling ozone can cause irritation to the mucous membrane and respiratory system. Ozone can also cause chest constriction and damage to vegetation. Other components of photochemical smog include:

• Nitrogen dioxide (NO2)
• Peroxyacetylnitrate (PAN)
• Aldehydes

Other air pollutants that can be harmful to humans include:

• Sulfur dioxide
• Volatile organic compounds (VOCs)
• Dioxins
• Polycyclic aromatic hydrocarbons (PAHs)

Carbon monoxide can cause hyperventilation, respiratory distress, and stillbirths. At high levels, carbon monoxide can even cause direct poisoning.

This question is part of 40000+ General Studies MCQ Series Course on GKToday Android app. Question Number: 3 in Chemistry-18-Important Non-Metals in above course in App.