FC chemistry of the troposphere Flashcards
Which species are liberated from earth
H2S, SO2
Which species are generated in thunderstorms
CO, NO
Which species are generated by living organisms
CH4, N2O
Describe the species in the troposphere
All the species contain elements in their lower oxidation states and are relatively insoluble in water
What does tropospheric chemistry generally involve
Tropospheric chemistry generally involve oxidation steps making species more soluble (CO2 from CH4, N2O5, SO3) and yielding acids in solution (H2CO3, HNO3, H2SO4)
Which radicals dominate tropospheric chemistry
OH and NO3 radicals dominate tropospheric chemistry while O species dominate in the stratosphere
Describe chemistry of the troposphere
Lots of radical change reactions. Some species (N2O, CH3Cl) survive the cycle and are transported to the stratosphere where they yield the NOx, HOx and ClOx radicals involve in the ozone cycle
What sort of process is oxidation and describes the steps of this process
Oxidation takes the form of a radical chain process
Initiation -> propagation -> termination
When can direct reactions with O2 not occur
At atmospheric temperatures
What is a primary process in photochemical kinetics
A primary process is the direct interaction of a molecule with light, leading to an excited state or bond dissociation. This is the initial step in a photochemical reaction.
What is a secondary process in photochemical kinetics
A secondary process involves subsequent chemical reactions after the primary photochemical event. These reactions don’t require light but are triggered by the reactive species generated in the primary step.
What is the main source of O3 in the troposphere
NO2 photolysis
Which sulphur species do biogenic emissions produce
Reduced species CS2, COS, H2S, DMS
Which sulphur species do volcanic emissions produce
Reduced and oxidised SO2 species
Which sulphur species do anthropogenic emissions
Oxidised SO2 species
