#pyrotecnics

Unbelievable Fireworks Show in 1 Minute | #shorts #fireworks

All fireworks rely on a combustion process that has 3 basic requirements: some sort of fuel to burn, a supply of oxygen, & a source of energy to initiate a reaction between the fuel & the oxygen. In the case of fireworks, the oxygen comes not from the air but is supplied by substances that release it by means of a chemical reaction. The earliest known oxygen supplier (“oxidizing agent”) was potassium nitrate (KNO₃), better known as saltpeter. The ancient Greeks discovered this substance & its value in warfare when mixed with a fuel such as sulfur or oil. It was difficult to extinguish due to the continuous production of oxygen. Greek fire struck fear into the hearts of their enemies.

But that was nothing compared to gunpowder. An ancient recipe was made based on the Chinese observation that a mixture of saltpeter, sulfur & charcoal was highly flammable. The Chinese used this mix as a propellant in primitive rockets made of bamboo poles. Those were the forerunners of our modern missiles & fireworks. When a pile of black powder is ignited, it noiselessly produces white smoke, which is actually tiny suspended particles of carbon. If the same powder is sealed inside a cardboard tube & ignited, it produces a bang. The noise is created by the rapid generation of a gas at high temperature, which in turn causes the surrounding air to move at the speed of sound. This is a firecracker. Light the same powder after it has been compressed into a tube with one end open & we have a rocket.

A firework is a rocket in combination with a firecracker.  When the rocket is ignited, the hot gases generated by the burning black powder are jetted out the open end, propelling the vehicle skyward. A timed fuse ignites the gunpowder in the firecracker part at an appropriate height, & we hear noise & see smoke. When substances are heated, they absorb some of the heat & get hot. The absorbed energy can then be released in the form of light. Different substances absorb & therefore emit different amounts of energy. We perceive these emissions as different colors. Sodium, for example, when heated, gives off a yellow color. Strontium produces a stunning red color. Magnesium, a brilliant white. Barium, a striking green color.  So yellow, red, green, & white colors are produced by adding the appropriate metals to the mix of fuel & oxidizer.

Blue, that’s a problem. A deep blue color is the ultimate challenge for the pyrotechnic designer. Copper monochloride can do it if the temperature is just right. But if it’s not, then it’s converted to copper compounds that emit either red or green colors. The flame temperature can be controlled by using the right mix of oxidizing agents, a tricky business. Especially because potassium chlorate is so dangerous that its use has been banned in England. It can accidentally ignite or explode, as it is very sensitive to friction, impact, or contamination & has caused burns, blast injuries, loss of fingers or hands & fatal explosions to workers. A mask must be worn because inhalation can be toxic.