The gaiety and joy experienced at the sight of the fireworks in the night sky are unparalleled. However, along with the visual treat, the science behind 'what causes fireworks to explode' is very intriguing and interesting...
What Causes Fireworks to Explode
Little compares to the visual treat that fireworks provide at any celebration; be it Christmas, New Year's Eve, birthday celebrations or an event to commemorate a victory. Fireworks are explosive pyrotechnic devices, lowered in impact, and used mainly as aesthetic assets. The displays involve the right co-ordination of the various components at regular intervals to light up the late evening or night sky, with colors of every hue or shade. They are mainly used for entertainment purposes. The show is nothing but a pyrotechnic and the collaborated effect by numerous firework devices. The science behind fireworks involve a rational understanding of the noise, smoke, light and materials that remain air-borne for a while. The basic design involves the directive to ensure colored flames and sparks to add to religious and cultural celebrations.

What Causes Fireworks to Explode:

Fireworks are classified as ground or aerial. They are accordingly designed to include a propulsion and mortar. There is always a pasteboard tube that houses the combustible material, like pyrotechnic stars. In order to display a consistent show of sparkling shapes and colors, the casements are ignited together. The science behind the spectacle involves basic components, such as:

1. A tube comprising explosives packed in black powder.
2. Treated string or a fuse, on top of the tube.

The color or colors of the firework and the noise factor (popping or whistling) largely depends on the kind of explosives filled within the tube. The components are commonly metallic salts and a predetermined placement of the explosives. Once the fuse is lit, the black powder compartment or container is ignited. The result is a release of gas that pushes the stars or tubes or whatever design material is filled, upwards.

The explosives used in fireworks are chemicals. Different chemicals are used to highlight different colors during the display. The commonly used ones are aluminum for silver and white, calcium sulphate for orange and red, copper carbonate for blue and cryolite for a bright yellow. While the addition of sodium salicylate creates the pleasant whistling noise, calcium silicide generates the smoke.

Making of Fireworks:

Firecrackers or fireworks have been around for centuries. The main chemical component, the world over, is either black (gun) powder or flash powder. The only difference in sparklers is that an oxidizer is used along with either iron or steel powder, to produce the sparkling stars. Among oxidizers, potassium nitrate is a common additive, while the common fuel components include charcoal and sulfur. The 'binder' commonly used is either sugar or starch. All the ingredients are mixed with water. The result is a slurry mixture that could either be poured into the paper compartment that will ultimately be fitted within the final design or coated on a metal wire, like in the case of sparklers. On drying, the fuel and oxidizer get proportioned with the other chemical additives. The metal flakes included for color and noise keep heating till incandescent.

Fireworks add that additional 'spark' to any celebration. The working or design of the individual pieces are in no way complex or out-of-bound. They are preplanned and executed within a predetermined order to define the color scheme and noise effect desired. The science behind the explosives is simple and the same as used in rockets, except for the chemical components and impact.

By Gaynor Borade