Strontium salts, fireworks

Calcium carbonate gives an orange flame, and often is used for toy fireworks etc. as a substitute for strontium salts. 

GUNPOWDER, or black powder, is a mixture of saltpetre, sulphur and carbon. Early Chinese recipes used equal weights to make a fast burning, but not explosive, powder. A composition that matches well the chemistry ctf the reaction is 15 parts saltpetre, 2 parts sulphur and 3 parts charcoal. Mix the ingedients while damp, using pressure to make a dense cake which can be broken into grains when dry. For most explosive results use refined saltpetre. Metal salts can add colour to the explosion, e.g. sodium salts for yellow or orange, potassium salts for purple, and strontium salts for red. This is the basis of fireworks. 

Strontium salts are used in fireworks and flares, which show the characteristic red glow of strontium in a flame. Strontium chloride is used in some toothpastes for persons with sensitive teeth. The metal itself has no practical uses. 

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. 

Yellow colors in fireworks are due to sodium. Strontium salts give the red color familiar from highway safety flares. Barium salts give a green color. 

The brilliant red colors seen in fireworks are due to the emission of light with wavelengths around 650 nm when strontium salts such as Sr(N03)2 and SrCOj are heated. (This can be easily demonstrated in the lab by dissolving one of these salts in methanol that contains a little water and igniting the mixture in an evaporating dish.) Calculate the frequency of red light of wavelength 6.50 X 10 nm. 

Yellow colors in fireworks are due to the 589-nm emission of sodium ions. Red colors come from strontium salts emitting at 606 nm and from 636 to 688 nm. This red color is familiar from highway safety flares. Barium salts give a green color in fireworks, due to a series of emission lines... 

The heavier alkaline earth ions give off characteristic colors when heated in a hot flame. Strontium salts produce the brUliant red color in fireworks, and barium salts produce the green color. 

In a typical fireworks device, the heat of the reaction between a strong oxidizing agent, such as KCIO4, and an organic compound excites certain salts, which emit specific colors. Strontium salts have an intense emission at 641 nm, and barium salts have one at 493 nm. (a) What colors do these emissions produce ... 

Yellow colors in fireworks are due to the 589-nm emission of sodium ions. Red colors come from strontium salts emitting at 606 nm and from... 

The alkaline earth metals can be detected in burning compounds by the colors that they give to flames. Calcium burns orange-red, strontium crimson, and barium yellow-green. Fireworks are often made from their salts (typically nitrates and chlorates, because the anions then provide an additional supply of oxygen) together with magnesium powder. 

When strontium metal is exposed to water, it releases hydrogen, as do the other earth metals (Sr + 2HjO —> Sr(OH)2 + H T). Strontium can ignite when heated above its melting point. When in a fine powder form, it will burn spontaneously in air. It must be stored in an inert atmosphere or in naphtha. Several of its salts burn with a bright red flame, making it useful in signal flares and fireworks. 

Chemical ingredients of fireworks are chosen to produce specific colors. Barium compounds produce green colors when heated, copper salts produce green and blue flames, sodium salts are yellow in flame, lithium compounds produce red colors, magnesium metal produces brilliant white fight when burned, and strontium compounds produce brilliant red colors. Salts used contain both metallic cations and nonmetallic anions. Anions such as chlorates, perchlorates, and nitrates also contribute oxidizing power to the chemical mixture. 

The red color in fireworks is the result of having strontium-containing salts in the fireworks bomb. Similarly, the green/blue colors sometimes seen in fireworks arise from copper salts. Based on your understanding of atomic spectra and the colors in fireworks, describe which atom, copper or strontium, has more widely separated energy levels. 

Various metals emit distinctive colors of visible light when heated to a high enough temperature (flame test). This is the basis for all fireworks, which use the salts of different metals such as strontium (red), barium (green), and copper (blue) to produce the beautiful colors. 

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