the magical world of fireworks

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The MagicalWorld of

Fireworks



Introduction of

Fireworks

A Brief History



Even before special occasions such as New Year·s Day, everyone has been preparing to

launch the much-awaited light spectacle in the night sky ² the Fireworks. These amazing,

magical fireworks never fail to excite and amaze people of all ages with its bombastic and

sparkling display of color and light.

But have you ever wondered how this magic works? When and where it was invented?

And what components does it have to make it burst into different colors?

Legend tells of a Chinese cook who accidentally spilled saltpeter into a cooking fire,

producing an interesting flame. Saltpeter, an ingredient in gunpowder, was sometimes used as a

flavoring salt. The other gunpowder ingredients, charcoal and sulfur, were also common in early

fires. When the mixture was burned with a little flame, it exploded if it was enclosed in a

bamboo tube. Rocket propulsion was common in warfare, as evidenced by the Huolongjing compiled by

Liu Ji (1311²1375) and Jiao Yu (fl. c. 1350²1412).[8] In 1240 the Arabs acquired knowledge of

gunpowder and its uses from China. A Syrian named Hasan al-Rammah wrote of rockets,

fireworks, and other incendiaries, using terms that suggested he derived his knowledge from

Chinese sources, such as his references to fireworks as "Chinese flowers".[9][1]

This surprising invention of gunpowder which appears to have happened about 2000

years ago, produced exploding firecrackers later during the Song dynasty (960-1279) by a

Chinese monk named Li Tian, who lived near the city of Liu Yang in Hunan Province. These

firecrackers were bamboo shoots filled with gunpowder. They were exploded with a loud noise

known as "gung pow" or "bian pao" at the commencement of the New Year to scare away evilspirits. By the 15th century, fireworks were a traditional part of other celebrations, such as

military victories and weddings. In 1110, a large fireworks display in a martial demonstration

was held to entertain Emperor Huizong of Song (1100²1125) and his court.

In 1240, the Arabs acquired knowledge of gunpowder and its uses from China. A Syrian

named Hasan al-Rammah wrote of rockets and fireworks and coined the term "Chinese

flowers".Arabians in the 7th century referred to rockets as Chinese arrows. Marco Polo was

credited with bringing gunpowder to Europe in the 13th century.

Most of the fireworks are made in the same way today as they were hundreds of yearsago. However, some modifications have been made. In 2004, Disneyland in California starting

launching fireworks using compressed air rather than gunpowder. Electronic timers were used

to explode the shells. That was the first time the launch system was used commercially,

allowing for increased accuracy in timing so that fireworks shows could be blended in with

music, and reducing smoke and fumes from big displays.



Process in

makingFireworks

Different Types of

Fireworks and its

Components



Firecrackers

Firecrackers are the original fireworks.

In their simplest form, firecrackers consists of gunpowder wrapped in paper, with a fuse.

Gunpowder consists of 75% potassium nitrate (KNO3), 15% charcoal (carbon) or sugar, and 10%sulfur. The materials will react with each other when enough heat is applied. Lighting the fuse

supplies the heat to light a firecracker. The charcoal or sugar is the fuel.

Potassium nitrate is the oxidizer, and sulfur moderates the reaction. Carbon from the

charcoal or sugar plus oxygen from the air and the potassium nitrate forms carbon dioxide and

energy. Potassium nitrate, sulfur, and carbon react to form nitrogen and carbon dioxide gases and

potassium sulfide. The pressure from the expanding nitrogen and carbon dioxide explode the paper

wrapper of a firecracker. The loud bang is the pop of the wrapper being blown apart.

Sparklers

A sparkler consists of a chemical mixture that is molded onto a rigid stick or wire. These

chemicals often are mixed with water to form a slurry that can be coated on a wire by dipping or

poured into a tube. Once the mixture dries, you have a sparkler.

Aluminum, iron, steel, zinc or magnesium dust or flakes may be used to create the bright,

shimmering sparks. An example of a simple sparkler recipe consists of potassium perchlorate and

dextrin, mixed with water to coat a stick, then dipped in aluminum flakes. The metal flakes heat up

until they are incandescent and shine brightly or at a high enough temperature actually burn. A

variety of chemicals can be added to create colors. The fuel and oxidizer, along with the other

chemicals, are proportioned so that the sparkler burns slowly rather than exploding like a

firecracker. Once one end of the sparkler is ignited, it burns progressively to the other end.

Rockets & Aerial Shells

Aerial shells are the fireworks that are shot into the sky to explode and burst off color and

light. Some modern fireworks are launched using compressed air as a propellent and exploded using

an electronic timer, but most aerial shells remain launched and exploded using gunpowder.

Gunpowder-based aerial shells essentially function like two-stage rockets:

The first stage of an aerial shell is a tube containing gunpowder, that is lit with a fuse much

like a large firecracker. The difference is that the gunpowder is used to propel the firework into

the air rather than explode the tube. There is a hole at the bottom of the firework so the

expanding nitrogen and carbon dioxide gases launch the firework into the sky.



The second stage of the aerial shell is a package of gunpowder, more oxidizer, and

colorants. The packing of the components determines the shape of the firework

This is a simple shell used in an aerial fireworks display. The blue balls are the stars, and the gray is

black powder. The powder is packed into the center tube, which is the bursting charge. It is also

sprinkled between the stars to help ignite them.

Simple shells consist of a paper tube filled with stars and black powder. Stars come in all shapes

and sizes, but you can imagine a simple star as something like sparkler compound formed into a ballthe size of a pea or a dime. The stars are poured into the tube and then surrounded by black

powder. When the fuse burns into the shell, it ignites the bursting charge, causing the shell to

explode. The explosion ignites the outside of the stars, which begin to burn with bright showers of

sparks. Since the explosion throws the stars in all directions, you get the huge sphere of

sparkling light.

The components of a modern firework include, from bottom to top, the following: launch

tube, lift charge, fuse, black powder, break, stars, time delay fuse. The launch tube is the steel

tube on the ground from which the firework shell is launched. The lift charge is the explosive at

the bottom of the firework shell that propels the shell into the air. The fuse consists of wires thatconnect the firework to a master control board; electrical current moves across the wires to create

a spark at the point of contact. Black powder is made up of potassium nitrate, charcoal (carbon),

and sulfur in a 75:15:10 ratio by weight. Breaks are the separate compartments in a firework shell

that contain a charge and stars. Stars are lumps made out of perchlorate, black powder, and the

chemical compounds that create the various colors of fireworks. The time delay fuses are the fuses

that burn down to the breaks and stars as the firework shell moves through the air.



Chemistry

Behind

Processes involved inMaking Fireworks



The processes that involve in the emission of light by fireworks are incandescence

(or the black body radiation) which is followed by first the atomic emission and then finally

the molecular emission that brings about the colorful emission:

Incadescence (Black Body Radiation)

The thermal radiation from a black body, an idealized physical body that absorbs all

incident electromagnetic radiation, is energy-converted electrodynamically from the

body's pool of internal thermal energy at any temperature greater than absolute zero. It

is called blackbody radiation and has a frequency distribution with a characteristic

frequency of maximum radiative power that shifts to higher frequencies with increasing

temperature. As the temperature increases past a few hundred degrees Celsius, black

bodies start to emit visible wavelengths, appearing red, orange, yellow, white, and blue withincreasing temperature. When an object is visually white, it is emitting a substantial

fraction as ultraviolet radiation.

Atomic emission

The process by which atoms emit certain, prefered wavelengths of electromagnetic

radiation. An atomic emission spectrum is made up only of a few lines of colour. The atomic

emission spectra are produced by thin gases in which the atoms do not experience many

collisions (because of the low density). The emission lines correspond to photons of

discrete energies that are emitted when excited atomic states in the gas make transitions

back to lower-lying levels.

Molecular emission

Molecular emission is the mechanism behind the sulfur lamp and the deuterium arc

lamp. The energy of a molecule can also change via rotational, vibrational, and vibronic

transitions. These energy transitions often lead to closely spaced groups of many

different spectral lines, known as spectral bands. Unresolved band spectra may appear as a

spectral continuum. The molecular emission spectrum of a chemical element or chemicalcompound is the spectrum of frequencies of electromagnetic radiation emitted by the

element's atoms or the compound's molecules when they are returned to a lower energy

state.



CreatingColors

And Light



Creating firework color requires considerable art and application of science. There

are two main mechanisms of color production in fireworks, incandescence and

luminescence:

Incandescence

Incandescence is light produced from heat. Heat causes a substance to become hot and

glow, initially emitting infrared, then red, orange, yellow, and white light as it becomes

increasingly hotter. When the temperature of a firework is controlled, the glow of

components, such as charcoal, can be manipulated to be the desired color (temperature) at

the proper time. Metals, such as aluminum, magnesium, and titanium, burn very brightly and

are useful for increasing the temperature of the firework.

Luminescence

Luminescence is light produced using energy sources other than heat. Sometimes

luminescence is called 'cold light', because it can occur at room temperature and cooler

temperatures. To produce luminescence, energy is absorbed by an electron of an atom or

molecule, causing it to become excited, but unstable. When the electron returns to a lower

energy state the energy is released in the form of a photon (light). The energy of the

photon determines its wavelength or color.

Sometimes the salts needed to produce the desired color are unstable. Barium chloride(green) is unstable at room temperatures, so barium must be combined with a more stable

compound (e.g., chlorinated rubber). In this case, the chlorine is released in the heat of

the burning of the pyrotechnic composition, to then form barium chloride and produce the

green color. Copper chloride (blue), on the other hand, is unstable at high temperatures, so

the firework cannot get too hot, yet must be bright enough to be seen.



Firework Colorants

Colors Elements Compounds

Intense Red Strontium SrCO3 (strontium carbonate)

Medium Red Lithium LiCl (lithium chloride)

Li2CO3 (lithium carbonate)

Orange Calcium CaCl2 (calcium chloride)

Yellow Soidum NaNO3 (sodium nitrate)

Cryolite, Na3AlF6

Green Barium BaCl2 (barium chloride)

Blue Copper CuCl2 (copper chloride) at

low temperature T urqouise Blue Copper CuCl (copper (I) chloride)

Indigo Cesium CsNO3 (cesium nitrate)

Violet Potassium KNO3 (potassium nitrate)

Red-Violet Rubidium RbNO3 (rubidium nitrate)

Gold Incandescence of iron (with carbon), charcoal, or lampblack

White Titanium, Aluminum, Beryllium, or Magnesium powders

Silver Burning Aluminum, Titanium, or Magnesium powder



Elements

used in

makingFireworks



Aluminum

Used to produce silver and white flames and sparks. It is a common component of

sparklers.

Antimony

Used to create firework glitter effects.

Barium

Used to create green colors in fireworks, and it can also help stabilize other volatile

elements.

Calcium

Used to deepen firework colors. Calcium salts produce orange fireworks.

Carbon

One of the main components of black powder, which is used as a propellent in fireworks.

Carbon provides the fuel for a firework. Common forms include carbon black, sugar, or

starch.

Chlorine

An important component of many oxidizers in fireworks. Several of the metal salts that

produce colors contain chlorine.

Copper

Its compounds produce blue colors in fireworks.

Iron

Used to produce sparks. The heat of the metal determines the color of the sparks.

Lithium

A metal that is used to impart a red color to fireworks. Lithium carbonate, in particular, is

a common colorant.



Magnesium

Burns a very bright white, so it is used to add white sparks or improve the overall

brilliance of a firework.

Oxygen

Fireworks include oxidizers, which are substances that produce oxygen in order for

burning to occur. The oxidizers are usually nitrates, chlorates, or perchlorates. Sometimes

the same substance is used to provide oxygen and color.

Phosphorus

Burns spontaneously in air and is also responsible for some glow-in-the-dark effects. It

may be a component of a firework's fuel.

Potassium

Helps to oxidize firework mixtures. Potassium nitrate, potassium chlorate, and potassium

perchlorate are all important oxidizers.

Sodium

Imparts a gold or yellow color to fireworks, however, the color may be so bright that it

masks less intense colors.

Sulfur

A component of black powder. It is found in a firework's propellant/fuel.

Strontium

Its salts impart a red color to fireworks. Strontium compounds are also important for

stabilizing fireworks mixtures.

T itanium

Its metal can be burned as powder or flakes to produce silver sparks.

Zinc

Used to create smoke effects for fireworks and other pyrotechnic devices.



Different

FireworksDisplays



The pattern that an aerial shell paints in the sky depends on the arrangement of

star pellets inside the shell. To create a specific figure in the sky, you create an outline ofthe figure in pellets, surround them as a group with a layer of break charge to separate

them simultaneously from the rest of the contents of the shell, and place explosive

chargesinside those pellets to blow them outward into a large figure. Each charge has to

be ignited at exactly the right time.

Palm: Contains large comets, or charges in the shape of a solid cylinder, that travel

outward, explode and then curve downward like the limbs of a palm tree

Round shell: Explodes in a spherical shape, usually of colored stars

Ring shell: Explodes to produce a symmetrical ring of stars

Willow: Contains stars (high charcoal composition makes them long-burning) that fall in

the shape of willow branches and may even stay visible until they hit the ground

Roundel: Bursts into a circle of maroon shells that explode in sequence

Chrysanthemum: Bursts into a spherical pattern of stars that leave a visible trail, with aneffect somewhat suggestive of the flower

Pistil: Like a chrysanthemum shell, but has a core that is a different color from the outer

stars

Maroon shell: Makes a loud bang

Serpentine: Bursts to send small tubes of incendiaries skittering outward in random

paths, which may culminate in exploding stars

the magical world of fireworks

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