Air Pollution Flashcards
characteristics of NOx
NO + NO2, forms ozone
characteristics of O3
colourless + odourless, main component in smog
what is combustion?
the burning of a substance in the presence of oxygen
what happens with complete combustion?
carbon dioxide + water produced
what happens with incomplete combustion?
carbon dioxide, water, and unwanted by-products produced
combustion of coal
CO, NOx, SO2, PM2.5, heat
what is fuel NOx?
reaction of oxygen with nitrogen in fuel
what are the main culprits in smog formation?
NOx and VOCs
sources of VOCs (3)
combustion - vehicles, construction
non-combustion - power plants, gas stations
natural - trees and plants
formula for formation of ground-level ozone
NOx + VOCs + sunlight = O3, PM, organics (secondary pollutants)
what pollutants are lung irritants and cause inflammation in the lungs?
NOx and O3
what do catalytic converters do?
reduce CO and NOx
when and where does the ozone hole appear?
Antarctica, every southern hemisphere spring (Sept-Nov)
qualities of UV-B
medium energy, reaches surface a medium amount, responsible for short-term, partially absorbed by ozone
qualities of UV-C
highest energy, doesn’t reach the earth’s surface, most dangerous, absorbed by compounds (mainly oxygen)
what does ozone protect from?
UV-C radiation (completely) and UV-B radiation (partially)
what was destroying stratospheric ozone? why?
CFCs and Halons, contain chlorine and bromine respectively
what were CFCs introduced to the market as?
Freon