How is energy in fuel released?

Answer 1

Chemical Energy is what is released.

Answer 2

The answer is implicit in the question, in that "heat" energy is released when something burns, however, the answer you're looking for may be "what sort of energy does fossil fuel contain?", and that is called Chemical Potential Energy (CPE). There is a certain amount of Energy available that is stored as chemical energy and not used until the correct conditions exist (heat, prescence of oxygen and source of ignition).

Once the CPE is released, the energy becomes an expanding cloud of hot residual gases possessing properties known as Heat Energy & Kinetic Energy (kinetic is something that moves) that can cause other things to move, such as a piston in a car's engine.

Answer 3

For fossil fuels, the energy resides in the chemical bonds between the carbon and hydrogen atoms of the hydrocarbon. When heat and oxygen are added to the hydrocarbon, the chemical bonds are broken and a great deal of energy is released (much more than the amount of energy initially added in the form of heat). This energy is often captured as heat energy which is used to turn water into steam that then drives a turbine around in a generator to make electricity.

In vehicles, the energy is captured as heat energy that increases the pressure within a piston chamber, which drives the piston upwards. The piston's movement is mechanically linked to the rest of the car and causes the wheels to turn.

Answer 4

chemical change and endothermic change

Answer 5

thermal energy.