Related topics: climate change , nasa , greenhouse gas
Carbon dioxide
hideCarbon dioxide (chemical formula: CO2) is a chemical compound composed of two oxygen atoms covalently bonded to a single carbon atom. It is a gas at standard temperature and pressure and exists in Earth's atmosphere in this state.
Carbon dioxide is used by plants during photosynthesis to make sugars, which may either be consumed in respiration or used as the raw material to produce other organic compounds needed for plant growth and development. It is produced during respiration by plants, and by all animals, fungi and microorganisms that depend either directly or indirectly on plants for food. It is thus a major component of the carbon cycle. Carbon dioxide is generated as a by-product of the combustion of fossil fuels or the burning of vegetable matter, among other chemical processes. Large amounts of carbon dioxide are emitted from volcanoes and other geothermal processes such as hot springs and geysers and by the dissolution of carbonates in crustal rocks.
As of March 2009[update], carbon dioxide in the Earth's atmosphere is at a concentration of 387 ppm by volume. Atmospheric concentrations of carbon dioxide fluctuate slightly with the change of the seasons, driven primarily by seasonal plant growth in the Northern Hemisphere. Concentrations of carbon dioxide fall during the northern spring and summer as plants consume the gas, and rise during the northern autumn and winter as plants go dormant, die and decay. Carbon dioxide is a greenhouse gas as it transmits visible light but absorbs strongly in the infrared and near-infrared.
Carbon dioxide has no liquid state at pressures below 5.1 atmospheres. At 1 atmosphere (near mean sea level pressure), the gas deposits directly to a solid at temperatures below −78 °C and the solid sublimes directly to a gas above −78 °C. In its solid state, carbon dioxide is commonly called dry ice.
CO2 is an acidic oxide: an aqueous solution turns litmus from blue to pink. It is the anhydride of carbonic acid, an acid which is unstable and is known to exist only in aqueous solution.
CO2 is toxic in higher concentrations: 1% (10,000 ppm) will make some people feel drowsy. Concentrations of 7% to 10% cause dizziness, headache, visual and hearing dysfunction, and unconsciousness within a few minutes to an hour.
For more information about Carbon dioxide, read the full article at
Wikipedia.
This text uses material from Wikipedia and is available under the GNU Free Documentation License.
News tagged with carbon dioxide
Acid test: Study reveals both losers and winners of CO2-induced ocean acidification
Space & Earth / Earth Sciences
Dec 01, 2009 |
4.4 / 5 (10) |
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(PhysOrg.com) -- As the world’s seawater becomes more acidic due to rising atmospheric carbon dioxide, some shelled marine creatures may actually become bigger and stronger, according to a new study.
Peat fires drive temperatures up
Nov 30, 2009 |
3.4 / 5 (5) |
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Peatlands, especially those in tropical regions, sequester gigantic amounts of organic carbon. Human activities are now having a considerable impact on these wetlands. For example, drainage projects, in combination with the ...
Australian scientists aim to reduce sheep burps
Nov 29, 2009 |
2.2 / 5 (6) |
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Australian scientists are working to breed a sheep that belches less, as they look for ways to reduce harmful methane emissions from the country's woolly flocks, a researcher said Sunday.
Search results for carbon dioxide
Discovery opens new avenues for treating devastating freshwater fish parasite, 'Ich'
8 hours ago |
4.8 / 5 (4) |
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Researchers from the University of Georgia College of Veterinary Medicine have made an "unexpected" dual discovery that could open new avenues for treating Ichthyophthirius multifiliis, or "Ich", a devastating ...
Maryland Farmer grows plants for green roofs around nation
12 hours ago |
3.8 / 5 (4) |
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It is a crisp fall day on Emory Knoll Farms as John Shepley stops at a raspberry bush, picks a few berries and pops them into his mouth on his walk to the greenhouses.
UK climate scientist to temporarily step down
Dec 01, 2009 |
3.6 / 5 (7) |
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(AP) -- The chief of a prestigious British research center caught in a storm of controversy over claims that he and others suppressed data about climate change has stepped down pending an investigation, the ...
First comprehensive review of the state of Antarctica's climate
Space & Earth / Earth Sciences
Dec 01, 2009 |
3.7 / 5 (11) |
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The first comprehensive review of the state of Antarctica's climate and its relationship to the global climate system is published this week by the Scientific Committee on Antarctic Research (SCAR). The review - Antarctic ...
Superior Super Earths
Space & Earth / Space Exploration
Nov 30, 2009 |
4.8 / 5 (43) |
14
Super Earths are named for their size, but these planets - which range from about 2 to 10 Earth masses - could be superior to the Earth when it comes to sustaining life. They could also provide an answer to ...
Naked mole rats may hold clues to surviving stroke
Nov 30, 2009 |
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0
Blind, nearly hairless, and looking something like toothy, plump, pink fingers, naked mole rats may rank among nature's most maligned creatures, but their unusual physiology endears them to scientists.
Sharp shows plant making 10th generation panels
Nov 30, 2009 |
4 / 5 (1) |
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(AP) -- Huge sheets of glass are guided by robotic arms, sliding and turning in a towering germ-free plant, the world's first making giant "10th generation" panels for flat screen TVs.
List of search results for carbon dioxide
