NEET2014BotanyEnvironmental IssuesActual
Photochemical smog formed in congested metropolitan cities mainly consists of
Options
- Aozone, peroxyacyl nitrate and NO _ x
- Bsmoke, peroxyacyl nitrate and SO ₂
- Chydrocarbons, SO ₂ and CO ₂
- Dhydrocarbons, ozone and SO _ x .
Correct answer
A. ozone, peroxyacyl nitrate and NO _ x
Step-by-step solution
Photochemical smog is a grey or yellowish brown opaque smog having oxidizing environment but little smokes. It is formed at high temperature over cities and towns due to still air, emission of NO ₂ oxides and hydrocarbons from automobile exhausts. Nitrogen dioxide splits into nitric oxide and nascent oxygen. Nascent oxygen combines with molecular oxygen to form ozone. Ozone reacts with hydrocarbons to form aldehydes and ketones. Nitrogen oxides, oxygen and ketones combine to form peroxy-acyl-nitrates (PAN).