Fireworks invove a lot of chemistry and physics Fireworks involve a lot of chemistry and physics. To project the explosivesup requires conversion of chemical energy to kinetic energy that overcomesgravity. When they explode, chemical energy is converted to mostly lightand sound. The symmetry the fragments display is a consequence of the conservationof momentum. The sum of the momenta before and after explosion iszero.
Gravity makes the pojectiles follow an inverted parabola.