What type of energy is released when a firecracker explodes

- - Sound energy. That's how you hear it explode.

- - Light energy. That's how you see it in the sky.

- - Heat energy. That's why you get burned if sparks fall on you.

- - Potential energy, as all the pieces fall to the ground.

These were all stored in it as chemical energy before it exploded.

There is heat, light and sound energy, that is released.