Monday, 16 October 2017

The Chemistry of FireCrackers

we all love fireworks. we can look unto them for many many hours and hope that it never finishes. fireworks are so mesmerizing? The sudden, bright, moving sparks they emit are compelling to watch and seem mysterious because we’re so unused to light of that type travelling directly into our eyes. In general, the colors we see are created by light bouncing off the reflective surfaces of objects around us. As we encounter this reflected light all the time, we’ve become very good at unscrambling the colors in our brain and, as a result, anything different can seem otherworldly. This could be why other sources of moving light, like shooting stars and fireflies, are also thought of as magical..

But do you know, how it is made, from where those tiny little flare, colorful flare i will tell You the chemistry behind fireworks.You can actually make some of them in home from little material available. so let's start. Diwali is coming and everyone is so exited.
what is a Firecracker

Many of you already familiar with A firecracker (cracker, noise maker, banger). It is a small explosive device primarily designed to produce a large amount of noise, especially in the form of a loud bang; any visual effect is incidental to this goal. They have fuses, and are wrapped in a heavy paper casing to contain the explosive compound. Firecrackers, along with fireworks, originated in China.
How it's Made
The Chemistry of fireworks is based on the simple theory of combustion. The composition inside the firework must however contain 6 vital ingredients:

Fuel : Charcoal, commonly known in the pyrotechnic industry as black powder is the most common fuel used in fireworks. Normally, all fuels will contain an organic element such as charcoal or thermite.

The mechanism by which the fuel functions in the firework is relatively simple. The fuel loses electrons to atoms within the oxidiser (thereby reducing the oxidiser) and releasing atoms from the oxidiser. During this process, bonds are formed between the fuel and oxygen atoms forming a product which is relatively stable. However, only a minimal amount of energy is required to start the combustion of this fuel-oxidiser compound. When combustion does start, the result is a massive release of energy as the solid mixture liquefies and vaporises into the flame of ignition. This maximises the probability of reaction of the oxidiser as it is brought into the close proximity of the flame.
Oxidising Agents

Reducing Agents : The second part to a firework is the reducing agent. These burn the oxygen provided by the oxidising agents to produce hot gasses. Common reducing agents are Sulphur and Charcoal. These react with the oxygen to form Sulphur dioxide and Carbon dioxide respectively as illustrated below. By mixing both the reducing agents, the speed of the reaction can be controlled.

Regulators: Metals can be added to regulate the speed at which the reaction. The larger the surface area of the metal, the faster the reaction will proceed (collision theory).
Colouring Agents. Different chemicals are used to produce different coloured fireworks. Therefore, in order to produce a firework of a certain colour, the correct corresponding chemical or as the case may be, mixture of chemicals can be used. Hence Strontium used in conjunction with Copper will yield a purple firework.
The incandescence from the elements occurs when solid particles are heated in the flame to extremely high temperatures. These release excess energy in the form of light (hv) at the broad end of the spectrum. The higher the temperature, the shorter the wavelength at which light is emitted, and the nearer it tends toward the blue end of the coloured spectrum. This is why blue coloured fireworks are so hard to synthesise, as they only occur at very high temperatures.

Binders : Binders are used to hold what is essentially the mixture of the firework together in a paste like mixture. The most commonly used binder is known as dextrin, a type of starch which holds the composition together. Paron can also be used in binding, however it is less common and only used in conjunction with red and green fireworks as it helps to enhance their color. The binders do not actually begin to work until the firework has been lit as they are too unstable for storage within the firework and are hence potentially dangerous.

so now, when you know the chemistry of firecrackers, i hope burning crackers will me more joyful this year.also, if you like this article plz share it with your friends, and do not forget to check out my youtube channel i.e the random lesson. HAPPY DIWALI TO ALL OF YOU.

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