How is chemical energy stored in coal released?

The chemical energy in coal is generally released when it is burned in an oxygen-rich environment, mostly when carbon atoms in coal (usually bonded to other carbon atoms) combine with oxygen to form carbon dioxide or monoxide. read more

It is stored in bonds and released in energy. Energy is needed to break the chemical bonds, and energy is released when bonds are broken. read more

Usually, once chemical energy is released from a substance, that substance is transformed into an entirely new substance. For example, when an explosive goes off, chemical energy stored in it is transferred to the surroundings as thermal energy, sound energy and kinetic energy. read more