Methane is an alkane with the chemical formula CH4. As a hydrocarbon, it can undergo hydrocarbon combustion which gives off heat. Methane is the main hydrocarbon component of natural gas, which is a type of fossil fuel.
At typical temperatures and pressures it is a gas and makes up around 95% of the content of liquefied natural gas, and around 80-90% of natural gas. Methane is also a greenhouse gas, like carbon dioxide (CO2). It has a shorter atmospheric lifetime than CO2, at 12 years, but this is "balanced" by the fact that it is more effective at trapping heat than CO2, as methane has a GWP (Global warming potential) of 21.
Methane combustion (see simulation at bottom of page) provides a significant fraction of the world's primary energy, and is used for home heating, cooking food, heating water, and electrical generation. It can even provide energy for transportation. However, this means that it is also a significant contributor to climate change since this methane produces a fair amount of the carbon dioxide that humans emit into the atmosphere.
Below is a table of some of the basic properties of methane.
|Molar mass||16.04 grams/mole|
|Energy density||55.5 MJ/kg|
|Atmospheric lifetime||12 years|