On July 4, Independence Day, thousands of fireworks lit the sky over the United States. However, out of millions of viewers, few people think that ordinary chemistry is behind this magnificent performance - a combination of various chemicals.
John Conkling, a professor of chemistry at the College of Washington, showed a video of the chemical constituent of the fireworks for members of the nonprofit American Chemical Society.
Without chemistry, there is no burning mixture, and without a burning mixture, there are no fireworks, - said D. Conkling. - The color in the fireworks is determined by the combination of a whole spectrum of metal salts. For example, copper gives blue when burning, while strontium and magnesium give red and white.
Before the fireworks are launched into the sky, the metal salts are packed into plum-sized granules ("stars"). After launch, ignition occurs and the starting charge throws fireworks into the sky, simultaneously igniting the detonator cord. The burned out cord activates the main charge, which, when detonated, crumbles into many multi-colored lights.
The American Pyrotechnics Association notes a steady increase in the demand for fireworks. So only on July 4, it is expected that the Americans will spend at least $ 755 million on their individual fireworks in honor of the country's main holiday.