Transcript CarbDioxREV12

Carbon Dioxide
(CO2)
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What is it?
A gas
Odorless
Colorless
Tasteless
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Where is it?
In the air around us
In water
In our breath
In our blood
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Sources of CO2
Combustion (burning)
Cellular respiration in
living beings
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Combustion (Burning)
In wood stoves, engines, power
plants, wildfires
Fuel: wood, paper, oil, gas, coal
Oxygen required (rapid oxidation)
Energy released
CO2 released as waste product
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Cellular Respiration
In cells of plants, animals, fungi,
microbes
Fuel: sugar
Oxygen required (gentle oxidation)
Energy released
CO2 released as waste product
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How does nature use CO2?
Used by plants
Raw material for photosynthesis
Plants need CO2 + water to make
sugar
Energy required (sunlight)
Oxygen released as waste product
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Photosynthesis & Respiration
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Respiration + Photosynthesis
They form a circle
One is reverse of the other
Waste products from one =
raw material for other
Gases are recycled
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Gases Recycled
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CO2 in Water
pH lab: exhaled breath decreased pH
of water
CO2 dissolves, forms carbonic acid
Can cause pH of water to decrease
Water may become more acidic
Carbon dioxide lowers pH of rain
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CO2 in the Atmosphere
One of the “greenhouse gases”
Acts like glass in a greenhouse
Helps to keep earth warm
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How much carbon dioxide?
0.03 percent by volume in
earth’s atmosphere
Increasing due to
Burning
of fossil fuels
Cutting of forests
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Is carbon dioxide
good or bad?
Natural part of our world
Essential for plant photosynthesis
Greenhouse gas
What about “global warming”?
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For More Information
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EPA Climate Change impacts & info by region
• Website: www.epa.gov/globalwarming/
EPA/DOE ENERGY STAR® program
• Energystar Hotline: (888) 782-7937
• Website: www.energystar.gov
Global Climate Change Impacts in the U.S.
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Website: www.globalchange.gov
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