Chem2 Flashcards
4 major components of dry air
nitrogen, oxygen, argon, carbon dioxide
nitrogen fixation done by
lightning. N2+O2–>2NO. then reacts further with oxygen and water to form nitrous and nitric acids
thermosphere
ionosphere. warms with altiutude because of ions from sun. auroras
warming in stratosphere
uv radiation from sun triggers exothermic reactions. more UV is closer to sun so increaseds with altitude.
low pressure at?
high altitudes
how do barometers work
mercury pumped easier at high pressure. cant pump in alps (galileo and torricelli)
Why does the egg go into the bottle?
Pressure outside was greater than pressure inside. outside greater due to production of more gas
thermosphere charged particles
e+O
p+N2 charges those and gives off light as they go back to regular forms (down in energy level).
space shuttle glow
O+NO—> NO2* excited, goes back to regular form, gives off orange tail
chapman cycle
creation and destruction of ozone. no net change in concentration O2+UV-->2O O2+O-->O3 O3+UV---> O2+O O3+O-->2O2
ozone thickness
only 3mm thick. stretches about 30 miles though.starts at 20-30km. not pure ozone. Just in a high concentration
UV A
lest energy, longest wavelength, least damaging, greatest amount reaching earth
UV B
more damaging, most absorbed by ozone in atmosphere. 200-300nm. 97-99 blocked%
UV C
most energy, shortest wavelength, most damaging. totally absorbed by oxygen/ozone. No makes it to the service
UV radiation biological effect
damages DNA. UVB. increase in melanoma.
variations in ozone levels
vary every 12 years due to solar intensity/sunspot activity, seasonal variation, 10% decrease over past 3 decades
ozone depletion where?
Antarctica
what can destroy the ozone
additional trace gases
natural trace gases
hydroxyl radicals. unsatble and reactive with an unpaired electron. destorys in upper stratosphere. nitric oxide (NO) from lightning
anthropogenic (man-made) trace gases
from combustion- NO, jet engines. Chlorine radical from CFCS
CFCS
chlorofluorocarbons. refrigerants replacing ammonia and sulfur dioxide (corrosive and toxic)
CFC properties
nontoxic, nonflammable and unreactive in the troposphere (long half life). reactive in stratosphere.
Cl radical
catalyst, consumed and regernated as it destroys ozone. becomes clo (measure concentration of this and 03 over ozone)