Fossil fuel embedded energy is still photosynthetic in origin. Terrestrial plants, on the other hand, tended to form coal and methane. Many of the coal fields date to the Carboniferous period of Earth's history. Terrestrial plants also form type III kerogen, a source of natural gas. There is a wide range of organic, or hydrocarbon, compounds in any given fuel mixture. The specific mixture of hydrocarbons gives a fuel its characteristic properties, such as boiling point, melting point, density, viscosity, etc. Some fuels like natural gas, for instance, contain only very low boiling, gaseous components. Others such as gasoline or diesel contain
Ethanol fuel by country The first flex motorcycle was launched to the market by Honda in March 2009, and a second model in September 2009. By the end of 2009, both Honda flexible-fuel motorcycles had sold a total of 183,375 units, representing an 11.4% market share of the Brazilian new motorcycle sales in that year. Two other flex-fuel motorcycles manufactured by Honda were launched in October 2010 and January 2011. During 2011 a total of 956,117 flex-fuel motorcycles were produced, raising its market share to 56.7%. Cumulative production of the four available flex fuel models since 2009 reached 1.48 million units in December 2011.