Methane

  

Methane is a chemical compound with the molecular formula CH4. It is the simplest alkane, and the principal component of natural gas. Methane's bond angles are 109.5 degrees. Burning one molecule of methane in the presence of oxygen releases one molecule of CO2  dioxide and two molecules of H2O:

CH4 + 2O2 → CO2 + 2H2O

Methane's relative abundance and clean burning process makes it a very attractive fuel. However, because it is a gas (at normal temperature and pressure; see STP), methane is difficult to transport from its source. In its natural gas form, it is generally transported in bulk by pipe or LNG carriers; few countries still transport it by truck. One of these countries is the USA.

Methane is a relatively potent greenhouse gas with a high global warming potential (i.e., warming effect compared to carbon dioxide.The Third assessment report of the IPCCstated that when averaged over 100 years each kg of CH4 warms the Earth 25 times as much as the same mass of CO2. Fourth assessment report has updated this number to include indirect effects and states that the relative impact of CH4 to CO2 averaged over 20 years is 72.[2]. The reason for this discrepancy is that methane in the atmosphere is eventually oxidized, producing carbon dioxide and water. As a result, methane in the atmosphere has a half life of seven years (every seven years, the amount of methane halves).


Radiative forcing effect of methane is about one-third of that of CO
2rd of that of CO2 , which means that pound for pound it may trap more heat in the atmosphere than CO2, even though far more CO2 is actually emitted. However, there is a large, but unknown, amount of methane in methane clathratesin the ocean floors. Global warming could release this methane, which could cause a further sharp rise in global temperatures. Such releases of methane may have been a major factor in previous major extinction events. The Earth's crust also contains huge amounts of methane. Large amounts of methane are produced anaerobically by methanogenesis. Other sources include mud volcanoes which are connected with deep geological faults

 

   








 
 


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