Question

The secondary precursors of photochemical smog are

• A. $SO_2$ and $NO_2$
• B. $NO_2$ and hydrocarbons
• C. $O_3$ and $PAN$
• D. $CO_2$ and $O_2$

Answer 1

Answer: (C)

$O_3$ and $PAN$

Answer 2

The primary precursors of photochemical smog are $NO_2$ and hydrocarbons and the secondary precursors are ozone and $PAN$.