### fuel:

Coal
* All coal contains a percentage of ash
  - has carbon and sulfur to some degree
* More coal is produced in the state of Wyoming than in any other state in the United States.
* Most coal contains carbon
  - generates heat
* Most coal has aromatic structures
  - ring structures
  - increases pollution
* Most coal is derived from the remains of terrestrial plants
  - fossil peat
  - transported by trains to power plants where it's burned to make steam
  - mined today is bituminous
  - produced in the state comes from large underground mines
* Most coal produces carbon dioxide emissions
  - sulfur dioxide
  - releases dangerous gases
  - used in California comes from other states
* Some coal burns hotter and cleaner than other types of coal
  - causes allergic reaction
* Some coal contains mercury
  - pyrites
  - uranium
* Some coal has low permeability
  - selenium in it
  - sulphur
  - is used to make medicines, paint, and steel
  - lies near the earth's surface, and can be gathered off in strips
  - mixes with water
* Some coal produces carbon monoxide
* abounds and is extensively mined.
* accounts for about one quarter of energy consumption in the United States
  - three quarters of electricity generation
* always contains mineral impurities.
* are absent and plant assemblages are dominated by conifers
  - common locally
  - extensively worked
* are ready when covered with a light gray coating of ash
  - they glow and are covered with a white ash
* begins to replace wood and charcoal as preferred fuel in Britain.
* burning for domestic purposes is still widespread in the region, especially during winter
  - electric generation contributes greatly to greenhouse gases
  - produces gases that contain primarily carbon, sulfur, nitrogen, hydrogen, and oxygen
* burns to leave ash.
* can burn for days, sometimes even a week
  - re-ignite several hours after they appear to be cold
  - reignite several hours after they appear to be cold
* comes from anciently buried plants, and petroleum is from animals
  - mines, strip mines mainly
  - open pit or underground mines
  - in many forms ranging from hard, black colored rocks to soft brown dirt
* consists of carbon, shale and water
  - plants which have been reduced to almost pure carbon
  - excessive amount of carbon
  - many pollutants
  - mercury, a heavy metal
  - sulfur ions which are released when it burns
* contains sulfur, nitrogen, mercury and carbon, among many other mineral components
  - which combines with oxygen when the coal is burned to produce sulfur oxides
  - trace amounts of mercury that are released into the air as it is burned for energy
* continues to be at the foundation of the U.S. economy.
* fights natural gas.
* generates more than half of America's electricity supply
  - the nation's electricity
* glow red and warm when they touch each other.
* increases air pollution
* is blackness
  - by far the world's most plentiful, widely distributed and accessible fossil fuel
  - carbon mixed with minerals
  - complex because of the wide variety of factors that determine the quality of coal
* is located in beds
  - cellars
  - coal mines
  - fire
  - stockings
  - made of carbon
  - organic matter
  - produce most economically from large strip mines
  - used for energy
* lies under about a third of Pennsylvania.
* make the sweat smokey, and hard to breath.
* means carbon dioxide.
* occurs naturally in abundance in pre-anthropogenic sediments.
* often shows fossil patterns of ferns and leaves from the original plants.
* plays a critical role in Colombia's economy
  - key global role in energy and as an input to industry
  - more emissions per unit of energy than does natural gas
* provides more than half the nation's electrical energy needs.
  - mercury when it is burned
* supplies two-thirds of electricity generation.
+ Selenium, Occurrence: Chemical elements :: Nonmetals
  * This selenium is in selenides. Selenium is gotten as a byproduct. Sometimes selenium is concentrated in plants. It can also be leached into rivers when copper is mined. Too much selenium is bad for a river. Some coal has selenium in it.
+ Sulfur, Occurrence and preparation
  * Sulfur can be found in the earth near volcanoes. Many minerals contain sulfur ions. Coal contains sulfur ions which are released when it burns. Hydrogen sulfide and sulfur dioxide are some sulfur compounds that are released when coal burns. They are reacted to make sulfur.