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Unformatted text preview: r NOx!
Pollution from Transportation: i.e., the internal combustion engine
Many engines burn gasoline (a hydrocarbon).
Sulfur dioxide not produced in significant amounts: - gasoline contains almost no sulphur.
Not the case for diesel engines (hence labels on diesel pumps!)!
Engine exhaust pipe emissions contain: carbon monoxide, NOx, partly burnt fuel components (VOC’s),
PM & lead(outside the US). Engine emissions are also responsible for tropospheric ozone and some smog.
carbon monoxide: forms from incomplete combustion of carbon: 2C + O2 speed of process of combus/on 2CO allows for imperfec/ons thus incomplete combus/on oxides of nitrogen (NOx):
NO forms from nitrogen and oxygen gas present in the air sucked into the combustion chamber and the
extreme heat of the combustion: N2 + O2 2NO
NO converts back and forth to NO2 by a complex set of reactions (see below)
NO2 forms in urban areas from reaction of NO with ground level ozone: NO + O3
But it can break down in the sun (see later) to reform NO!!!...
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- Spring '08