FIREWORKS http://teachable.net/res.asp?r=1824

What are Fireworks made from? The first fireworks were made from gunpowder, (a mixture of ingredients including saltpetre, sulphur and charcoal.) Today, experts at handling explosives, called pyrotechnicians, add chemicals for special effects. Ingredients are placed in a shell, the whole thing is wrapped up and then a fuse is added.

How Do Fireworks Work? Rocket: When a rocket is lit, a substance explodes, creating gasses that shoot the firework into the air. When the firework reaches a certain height, another spark causes it to blow up, releasing fine metal powders into the air. Roman candles: These long tubes shoot balls of chemicals from one end, creating a series of flaming stars. Inside the tubes, the chemical balls are packed one on top of the other, with layers of sawdust between them. Fountains: These are cone-shaped and sit on the ground. A hole in the top allows gases to escape, shooting coloured sparks into the air.

How Do Fireworks Work? Smoke bombs: These fireworks create colourful smoke. Sparklers: These are long pieces of wire. Half of the wire is covered in chemicals that give off bright sparkles of light when lit. The sparks burn off at 1650°F, which is the same temperature as a welding iron. Sparklers have caused some of the most serious firework accidents. Aerial shells: These are used in professional displays. They are the most spectacular and usually the loudest fireworks. They are placed in a tube pointing towards the sky and launched by an explosion which shoots them into the air.

Colours Magnesium is the ingredient that gives off the bright white light in fireworks. This happens when the magnesium starts to burn when it comes into contact with the oxygen in the air. Other ingredients give off different types of light when they become hot. This how the colours in fireworks are created.

Firework Colour Chart (The science bit…) Red strontium salts, lithium salts Orange calcium salts Gold incandescence of iron (with carbon), charcoal, or lampblack Yellow sodium compounds Electric White white-hot metal, such as magnesium or aluminium Green barium compounds Blue copper compounds Purple mixture of strontium (red) and copper (blue) compounds Silver burning aluminium, titanium, or magnesium powder or flakes

Types of firework There are two basic types of fireworks: The type that you buy in shops, called consumer fireworks. The type used at firework displays, or professional use fireworks.

When were Fireworks invented? Fireworks are believed to have been invented by the Chinese. A Chinese document (from about 1040) showed how to wrap gunpowder in paper to make a 'fire pill.' This small firecracker made a very loud bang, which was believed to scare off evil spirits. Fireworks arrived in Europe in the 13th century. The popularity of fireworks grew, and by the early 1500s the army was lighting them for special events. The Italians were masters of fireworks through the 17th Century. Throughout Europe, Italian fireworks were used in religious festivals and other celebrations. Fireworks have become a traditional way to mark events all round the world.

When do we have big fireworks displays? In England, fireworks are used to celebrate November 5 - the anniversary of Guy Fawkes' failed attempt to blow up the houses of Parliament. Other countries use fireworks to mark the anniversary of different events. Here are a few of them: The signing of the US Declaration of Independence on July 4 The start of the French Revolution on July 14 The Chinese New Year, which is about a month after Jan 1. Diwali, the Hindu festival of lights, at the end of October or beginning of November The Jewish festival of Hanukkah, around December or January.

Firework Safety The most common firework injuries are caused by rockets, sparklers and air bombs. Lots of these injuries happened to children under the age of 16. Safety is very important and cannot be stressed enough when using fireworks. The Royal Society for the prevention of Accidents (RoSPA) advise that only adults should deal with fireworks and that children should watch from a safe distance. Also, packets of sparklers carry a warning: "Not to be given to children under 5 years of age." Adults using fireworks should follow the Firework Code.

Pets Pets get very frightened by fireworks, so keep all your pets indoors and close all the curtains.