How do fireworks explode ?

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These bright and festive chemistry experiments have been delighting people for hundreds of years
Despite their deffirent colours, shapes, speeds and sounds, all firworks have the same basic components Aerial firworks consist of a shell made of heavy paper that holds the"lift charge", the"bursting charge", and the the "stars"All of these glittery spectacles come from good old-fashioned combusion.
    Combusion is a chemical reaction between two substances(a fuel and and oxidant) that produces light and heat. The heat causes gasses to expand rapidly, building pressure. The  shells are tightly wrapped cylinders, which provide good resistance to this pressure, giving it a short time to build in intensity. Then, when the reaction overpowers the shell, you get the explosive firwork effect.
  It all starts when the shell is placed into a mortar(a cylinder the same size as the shell, which holds the firework in place while the fuse burns). The lift charge, at the bottom of the shell, is basiclly concentrated black power(charcol, sulphur, and potassium nitrate).
    when lit by the dangling fuse, the lift charge sends the shell into the air. Basic firecrakers are just paper-covered black powder: you light the fuse and listen to the popping sound. The bursting charge is another round of black powder with its own time-delayed fuse higher up in the shell. The bursting charge creates the heat to activate the stars that surround it and explode them outward from the shell. The stars are where the magic happens.
    Stars are balls made up of fuels, oxidisers, colour-creating combinations of deffirent kinds of metals, and a binder to hold everything together. The stars can be arranged within the firwork shell to create shapes. The shapes can be things like hearts, starts, and circles. Hundreds of stars can be used in a single firework shell.
     More complex fireworks - ones that produce a shape like a smiley face, have multiple phases of different colour, or make extra sounds like whistles, for exemple - have shels whith a more intricate in frastructure. In these types of  fireworks, these are more time-delayed fuses linked to various bursting charges with their own surrounding stars. Each of these may sit in its own individual interior shell. The are called "multi-break shells".
    While a sight to nehold, fireworks are individually wrapped chemistry experiments. Tapping one too hard or creating static electricity shock with your synthetic-material clothing could be deadly and one exploding near to your face could result in horrific burns and even blindness. They don't have the word 'fire' in them for nothing.