Elements of fireworks

The colors of fireworks displays are produced by emission from atomic ions as described in Chapter 7. The explosions of fireworks promote electrons to excited states. The energy level scheme of every element is different, so fireworks manufacturers can change colors by incorporating different elements. Sodium ions emit... 

Uses. Large quantities of Sb metal have been used mainly in alloys with Pb (battery grids) and other metals. Alloys are the predominant use of antimony because its brittleness bars direct use. High purity antimony (>99.999%) has a limited but important application in the manufacture of semiconductor devices. When alloyed with elements of 13th group (IIIA), the III-V compounds are formed these have important applications as infrared devices, diodes and Hall effect devices. Also used for fireworks and thermoelectric piles. 

Fireworks do not have frameworks like pictures. Accordingly the composition of fireworks must be specially considered. Fireworks are placed centrally in the space and all firework elements are concentrated towards the centre. Allternatively the elements are allowed to flow out of the centre. This is the rule in firework art, and is suitable for both cases one flower and a group of several flowers. 

Why are some fireworks red, some white, and others blue The key to understanding the chemical behavior of fireworks, and all matter, lies in understanding how electrons are arranged in atoms of each element. 

Bruno was an early atomist, writing on The Principles, elements and causes of things (1590), while Andreas Libavius (1597) developed the study of alchemy in two directions encheiria, the manipulation of materials, and chymia, the preparation and classification of chemicals. Biringuccio (1540, Pirotechnia) wrote of fireworks, Agricola (1556, De re metallica) of metals, Neri (1612, L Arte Vetraria) of glass... 

The beauty of fireworks is a direct result of the skill of the manufacturer. Selection of the proper oxidant, fuel, and color-producing elements is critical to the production of a spectacular display. Packaging these chemicals in proper quantities so that they can be stored and used safely is an equally important consideration. 

In 1823, Herschel [15] in the Transactions of the Royal Society of Edinburgh published his observations of the colors of flames produced by the introduction of alkaline earth salts. The green color obtained with barium salts is due to BaOH and the reddish color characteristic of strontium salts is caused by SrOH. The red colors of fireworks can also be attributed to emission from SrOH [16]. It was not until the 1950s that modern flame studies [17, 18] identified the molecules that are responsible for the alkaline earth flame colors. In contrast to the alkaline earths, the flame colors of the alkali elements are produced by atomic emission. The formation of molecules such as CaOH and SrOH, in fact, greatly complicates the use of flame absorption and emission for the determination of the concentrations of alkaline earth elements in analytical chemistry. 

Each element has a characteristic line spectrum that can be used to identify the element. Note that line emission spectra can also be obtained by heating a salt of a metal with a flame. For instance, common salt (sodium chloride) provides a strong yellow light to the flame coming from excited sodium, while copper salts emit a blue-green light and lithium salts a red light. The colors of fireworks are due to this phenomenon. 

With a concentration of 370 mg kg in the 16km-thick Earth s crust, strontium (Sr) occupies 18th position in the frequency list of elements. Strontium occurs as four stable isotopes with atomic masses 84, 86, 87, and 88. The latter isotope, with a relative abundance of 83%, is the most widespread. Isotope-pure Sr is found as a daughter product of the Rb isotope in several minerals, and is used to determine the age of rocks. Celestine (SrS04) and strontianite (SrCOj) are of economic importance, with 250000-300000 tons of celestine being extracted in 1991. Sr has minimal technological importance, but is used as nitrate in the production of fireworks, as a hydroxide for the removal of sugar from molasses, as... 

There are two naturally occurring types of elemental phosphoms red and yellow. Red phosphorus is not absorbed and is essentially nontoxic, in contrast, yellow phosphorus (also called white phosphorus) is a highly toxic cellular poison. Yei-low/white phosphorus is a colorless or yellow wax-like crystaiiine solid, with a garliclike odor, and is almost insoluble in water. Although no longer a component of matches, yellow/white phosphorus is still used in the manufacture of fireworks and fertilizer and as a rodenticide. 

Fireworks. The different colors are created by the atomic spectra of different elements. 

Uses/Sources. Manufacture of rat poisons for smoke screens gas analysis fireworks in ammunitions such as mortar, artillery shells, and grenades the elemental material is produced as a by-product in the production of phosphate fertilizer it does not occur in the elemental state in nature... 

Chemical testing is carried out in an approved laboratory because the firework must first be dismantled. Wet methods of analysis are applied that involve analytical grade reagents to detect, in particular, the presence of chlorates in admixture with elemental sulfur. Sulfur-chlorate mixtures are banned in the UK, and one use of sulfurless gunpowder is in fireworks where chlorates are also present. 

Several metallic sulfide compounds have been used as fuels in pyrotechnic compositions. Antimony trisulfide, Sb 2S3, is a reasonably low-melting material (m.p. 548°C) with a heat of combustion of approximately 1 kcal/gram. It is easily ignited and can be used to aid in the ignition of more difficult fuels, serving as a "tinder" in the same way that elemental sulfur does. It has been used in the fireworks industry for white fire compositions and has been used in place of sulfur in "flash and sound" mixtures with potassium perchlorate and aluminum. 

The same sources that emit elemental phosphorus to air are also responsible for its emission to water. In its initial states of operation, the ERCO plant in Newfoundland, Canada, which produced white phosphorus, discharged 68-91 kg/day of colloidal white phosphorus into the Long Harbor inlet of Placentia Bay in Newfoundland. Elemental phosphorus was found in both the effluent water and the bottom sediment of Long Harbor (Davidson et al. 1987 EPA 1991). White phosphorus is also expected to be found in the effluents from user industries where it is converted into products such as phosphoric acid and phosphate, detergents, fireworks, insecticide, rat poisons, flotation agents, and red phosphorus (Idler et al. 1981). 

During the troubles in Northern Ireland only indoor-type fireworks could be purchased without a special license. Analysis of particles originating from the use of indoor-type fireworks showed only a few spherical particles the majority was large irregularly shaped flakes. The elements aluminum, barium, chlorine, chromium, iron, potassium, sulfur, and antimony were detected, all of which were at a major level. 

Analysis of particles originating from the use of outdoor fireworks revealed that the majority of the particles was irregular, many were crystalline, and many large flakes were present. A small proportion of the particles were spherical and physically resembled FDR particles. Elemental analysis showed the presence of aluminum, arsenic, barium, calcium, chlorine, copper, iron, potassium, magnesium, sodium, lead, sulfur, antimony, silicon, strontium, titanium, zinc, and zirconium. None of the particles detected would be confused with FDR particles as the primary FDR elements were always accompanied by elements that were clearly of non-FDR source. 

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