Download Common Gases

Common Gases
Nitrogen
• Found in all living things
– DNA
– Amino acids (building blocks of proteins)
– Wart removal
Nitrogen cont
• Most abundant gas in the atmosphere
– 80% by volume
• Properties: colorless, odorless, tasteless
• Forms of N on earth: ammonia, nitrates,
nitrites, & nitric acid
• Nitrogen cycle:
Ammonia
• Uses:
– Fertilizers, grease cutting agents, nylon,
refrigeration, atmospheres of Jupiter & Neptune
• Physical properties:
– Colorless, strong odor
• Soluble in water with which it forms strong
hydrogen bonds
• Haber process: N made from air to make
artificial fertilizer
Hydrogen
• Physical properties: colorless, odorless,
tasteless, low density
• Hydrogen as a fuel source – fuel cells
– Home heating & cars
• Sun and stars – H in the plasma state
• Hydrogen rich products – petroleum, natural
gas, wood and coal
Uses for Hydrogen
• Hydrogenated margarine
• Fuel cells
• Removing S impurities from gas & coal
Oxygen
• Physical properties:
– Colorless
– Odorless
– Required for all basic life processes
– Denser than air
– O2 is very active!!!
– Most abundant by weight in the earth’s
atmosphere, crust & water
Types of oxides
• Oxides – compounds containing O -2
• Peroxides – compounds containing O -1
• Superoxides – compounds containing O -1/2
Acid Rain
• Sulfur oxides or Nitrogen oxides (SOx and
NOx)
• When burning high sulfur coal, these are
released into the atmosphere and react with
water in clouds
• SO2 + H2O  acid rain
Oxygen uses:
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Removes impurities in steel
Oxygen-Acetylene torches for welding
Liquid O and H to lift space shuttles
Hospitals to treat breathing and heart
problems
Ozone
• Properties: poisonous blue gas with pungent
odor
– You may notice the smell during lighting storms or
near electrical machinery
• Absorbs ultraviolet portion of sunlight
– Ultraviolet light: causes chemical reactions in
plants and animal tissues
Ozone hole?
• Destruction of ozone is caused by CFC’s
(chlorofluorocarbons)
• As CFC’s rise into the atmosphere they break
down and the Cl attacks ozone
• Where are CFC’s found?
• Ozone layer is constantly changing depending
on the seasons, weather and volcanic
eruptions
• Regeneration occurs in the warmer months