Fireworks sk Slide 2: Fireworks were first used in China because people thought their loud sounds would scare away evil spirits. Eventually firework making developed into a profession, although at first they were only used by royalty and the rich for...
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Fireworks sk Slide 2: Fireworks were first used in China because people thought their loud sounds would scare away evil spirits. Eventually firework making developed into a profession, although at first they were only used by royalty and the rich for ceremonies and celebrations. Then in the Ming Dynasty fireworks were used more commonly and people started to use them on New Year’s Eve, like we still do today Slide 3: Inside each handmade firework are small packets filled with special chemicals, mainly metal salts and metal oxides, which produce many different colours. When heated, the atoms of each substance in the mix absorb energy, causing its electrons to rearrange from their lowest energy state to attain a higher energy level. As the electrons plummet down to their original energy level, the excess energy gets emitted as light. The recipe that creates blue, for example, includes varying amounts of copper chloride compounds, while red comes from strontium and lithium salts. Just lik
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