Sodium salts, 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. 

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. 

Although you might think that the chemistry of fireworks is simple, achieving the vivid white flashes and the brilliant colors requires complex combinations of chemicals. For example, because the white flashes produce high flame temperatures, the colors tend to wash out. Another problem arises from the use of sodium salts. Because sodium produces an extremely bright yellow color, sodium salts cannot be used when other colors are desired. In short, the manufacture of fireworks that produce the desired effects and are also safe to handle requires very careful selection of chemicals. ... 

The presence of intense lines in the spectra of a number of metals is the basis for flame tests, simple tests used to identify elements in ionic compounds in the absence of a precise analysis of a compound s spectrum. For example, the emission spectrum of sodium features two closely spaced, bright yellow lines. When a crystal of a sodium salt (or a drop of a solution containing a sodium salt) is put into a flame, the flame glows bright yellow (Figure 7.14 ). As Figure 7.14 shows, other metals exhibit similarly characteristic colors in flame tests. Each color represents an especially bright spectral emission line (or a combination of two or more such lines). Similar emissions form the basis of the colors seen in fireworks. 

Figure 7-4a shows a deposit of sodium chloride, or table salt—the most common sodium compound. Table salt occurs naturally in many foods. It is used to keep food from spoiling and to preserve foods for long-term storage, as shown in Figure 7-4b. These roles were especially important before the widespread use of refrigeration. Potassium chloride serves as a salt substitute for people whose intake of sodium must be limited. Potassium compounds are included in fertilizers because potassium is an important factor for plant growth and development. Potassium nitrate is used as an explosive for large-scale fireworks displays.

Specihcations ior saltpeter to be used in fireworks making call for a salt that ia clean, white and should be ground fine enough to pas through a sieve of 60 to 100 mesh. It should contain less than lit of sodium, calcium and n agnesium sails combined. 

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. 

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. 

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... 

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... 

Inorganic salts of perchlorate (e.g., ammonium, potassium, and sodium) are manufactured for a variety of applications in the United States. Most importantly, ammonium perchlorate, which is a strong oxidant, has been for many years (and continues to be) widely used as a component in solid fuel for rockets and missiles employed by NASA and the U.S. military, pyrotechnic fireworks, and ordinary matches. For reasons associated with its production and use, some quantities of ammonium perchlorate have been released into the aquatic environment over the years. All perchlorate salts are water soluble, and once in water, the perchlorate anion is extremely mobile and stable. At present, cost-... 

A Fireworks typically contain the salts of such metals as sodium, calcium, strontium, barium, and copper. 

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