Firework chemistry

The Chemistry of Fireworks.



Hello everybody,today i am talking about fireworks.Fireworks are usually made out of the following items; an oxidizing agent, a reducing agent, a coloring agent, binders and regulators. These this mixed together are what make up the basic fireworks.



Oxidizer:

The first thing in a firework is the oxidizing agent. These produce the Oxygen to burn the mixture. Oxidizers are usually nitrates, chlorates or perchlorates. The common oxidizers are nitrates. These are made up of a metal ion and the nitrate ion. I'll use potassium nitrate as an example. Nitrates only give up 1/3 of their oxygen.

The next Oxidizers are chlorates are also made up of a metal ion and then the chlorate ion. Chlorates give up all of their oxygen, causing a more spectacular reaction. Unfortunately this also makes the chemicals EXTREMELY explosive.

Perchlorates have more oxygen in them, but are less likely to explode if you drop them than are chlorates. Again these are made up of a metal ion and then the perchlorate polyatomic ion.



Reducing Agents:

The second elements of fireworks are the reducing agents. The reducing agents burn the oxygen produced by the oxidizers to produce hot gasses. Two examples of reducing agents are Sulfur and Charcoal(carbon). These react with the oxygen to form respectively Sulfur Dioxide and Carbon Dioxide.

Usually two reducing agents are combined. This results in speeding or slowing the reaction. Therefore, the reducing agents are used to control the speed of the reaction. Also, metals are often added to speed the reaction. The finer the powder the faster the reaction. This is because of one of the factors affecting reaction rates, concentration. If you set fire to wheat, it will burn slowly. If you set fire to wheat dust floating in the air, it will explode, this is shown when a grain elevator explodes. Also cornmeal is often used to slow down the reaction. These metals and the cornmeal are the regulators.




Binders:

The fourth element of fireworks are the binders. Binders hold the mixture in a lump. This lump is a star. In order to form a star, two main elements are used. These two are dextrine dampened by water, or a shellac compound dampened by alcohol. These are rolled and then cut, or the mixture is forced into a paper tube, and pushed out with a dowel. Then the stars are cut as they come out.So this is the awesome fireworks chemistry!!!






(GOOD TO KNOW:))



Origins of Black Powder

Gunpowder or black powder was invented in China by alchemists experimenting with a naturally-occurring salt, potassium nitrate, also known as saltpeter. Ironically, they were looking for an elixir of immortality. But in handling and heating the sensitive substance they inevitably discovered its explosive properties. The first known account of the use of gunpowder as a weapon dates to 1046 in China, describing a catapult-launched grenade, an incendiary bomb, and a smoke bomb. The Song Dynasty Emperor in 1067 banned the sale of saltpeter and sulfur to foreigners and nationalized the production of gunpowder.


Marco Polo is sometimes given credit for bringing gunpowder to Europe but that is unlikely. When Europeans invaded the Middle East during the Crusades, they encountered gunpowder weapons used by Moslem forces. Despite government control and attempts to keep the formula secret, gunpowder probably traveled the Silk Road from China to the Moslem world far earlier than Marco Polo's trip in the late 1200s. English philosopher Roger Bacon (1217-1292) is believed to the first Westerner to describe gunpowder and fireworks. By the mid-1300s, European armies were using crude cannons and other gunpowder weapons.

Gravity around the earth – why are you heavier at the equator?

After some research,i realise that you are NOT heavier in the equator as compared to the both poles because of centripetal acceleration you will weigh a tiny amount less at the equator than at the poles. Objects which are in motion like to go in a straight line and so it takes some force to make them go round in a circle. So some of the force of gravity is being used to make you go round in a circle at the equator (instead of flying of into space) while at the pole this is not needed. The centripetal acceleration at the equator is given by 4 times pi squared times the radius of the Earth divided by the period of rotation squared (4 timed pi2 times r/T2). The period of rotation is 24 hours (or 86400 seconds) and the radius of the Earth is about 6400 km. This means that the centripetal acceletation at the equator is about 0.03 m/s2 (metres per seconds squared). Compare this to the acceleration due to gravity which is about 10 m/s2 and you can see how tiny an effect this is - you would weigh about 0.3% less at the equator than at the poles!


There is a second reason that you are slightly lighter standing on the equator than at either the North or South pole.
The Earth is not a perfect sphere and is squashed because it is rotating.
Its equatorial radius is about 22 kilometres more than its polar radius.
When standing at a pole you are actually slightly nearer the centre of the Earth than on the equator as gravity reduces as distance increases and although this is very small it is a contributing factor. Incidentally you are slightly lighter when the Moon is overhead (tugging upwards on you like the tides) and heavier when it is the other side of the Earth pulling you downwards. Maybe ranging as much as 1 gram for the average person.

Hence,this is why i say that we weigh lighter on the equator as compared to the poles or countries near them.Thank you for your kind attention.