What is coal?

  1. hubpoint profile image60
    hubpointposted 5 years ago

    What is coal?


  2. krillco profile image93
    krillcoposted 5 years ago

    Check out this description: http://en.wikipedia.org/wiki/Coal

  3. Iznogoud profile image78
    Iznogoudposted 5 years ago

    A rock made up of carbon, oxygen, hydrogen and nitrogen. It is what remains of trees, plants, mosses and other vegetation which once grew on the earth's surface and were afterwards covered by layers of other rocks. Great pressure and chemical changes, lasting for hundreds of thousands of years, gradually drove out the larger part of the gases, so that coal, as we now know it, is mostly carbon, squeezed into a hard, compact form.