Atmosphere - Chemistry Flashcards
What is the composition for atmosphere?
78.1% Nitrogen
21% Oxygen
0.9% Argon
0.04% CO2
What are the other trace gases?
Neon, Helium, Methane, Krypton, Nitrous oxide etc
Troposphere
Extends from earths surface to about 11km above, being the most significant
Stratosphere
Extends from 11km to about 50km
What solar radiation reactions occur in the atmosphere?
Trace gas photolysis, and oxidizable trace gas photooxidation, and photochemical reactions.
What does E=hV describe?
The energy of a photon of visible or UV light
What is hV?
H describes plancks constant and V the frequency of electromagnetic radiation.
Plancks Constant
A universal constant defining quantum nature of energy ,rleating to photons energy and frequency.
Why does UV light break chemical bonds easier than visible light?
It has more energy.
What do photochemical reactions usually result in?
Excited State species and Free Radicals.
Excited State
A product of a photochemical reaction electrochemically more energized, chemically more reactive.
Free Radicals
Containing unpaired electrons
What is an example of radical formation in the atmosphere?
Excited state reaction with water vapour, producing two hydroxyl radicals.
