Question #66793

1 Answer
Jan 25, 2018

It is stored as chemical energy in the bonds between the particles and normally released as heat energy when burned.


Coal formed from immense tropical swamp-forests millions of years ago. Some of the plants when they died did not rot away completely leaving the carbon (from the #CO_2# they absorbed when alive and converted to carbohydrates by photosynthesis) to be compressed in bands for geological times to form coal.

When we burn it the carbon again bonds with oxygen to release heat energy in the reaction #C + O_2 rarr CO_2 + heat#

OK now?