Q. Which of the following is secondary pollutant?
A) $CO_{2}$
B) $SO_{2}$
C) ${NO}_{2}$
D) $H_{2}O$
Explanation
When primary air pollutants (gases, particulates) take part in wide range of photochemical reactions, they form secondary pollutants. Important secondary pollutants are${SO}_{2},H_{2}{SO}_{4}$ PAN etc.
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.