Methane is an abundant organic compound on earth. It is classified as a greenhouse gas, and is about 20 times more effective at trapping the suns radiation than carbon dioxide. It stays in the environment for anywhere between 9-15 years. Methane can be found in oil wells, agricultural sights, sewage, landfills, and underground gas reservoirs. Methane is also produced by animals such as cows, during the digestion process.
In its pure form, it is a colorless and odorless gas. It is used extensively as a heating fuel and contributes to the production of many chemicals such as acetic acid, ammonia, and methanol. It can be used as a compressed gas or a refrigerated liquefied gas.
It is basically non-toxic at low concentrations but extremely flammable. If contact occurs with methane in the liquid or compressed forms, cold burns and frostbite can result. Pure methane gas will not irritate the skin or eyes. However, at high concentrations, methane can be an asphyxiant by displacing oxygen in the blood.
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