What is the least loudest firecracker?

What burns in a firecracker?

• I have been taking apart M-100's and trying to find what burns inside of them. there's a hard compact light grey powder that fills most of the tube, m guessing thats just a filler. Then there is a small green tube that the fuse is attached to. Inside there is a dark gray and a reddish brown powder. I have tried lighting these powders but can't seem to. And yes im taking safety precautions.

• Answer:

  Firecrackers start with three main substances: 75 percent is made up of potassium nitrate, 15 percent is made up of carbon (charcoal) and 10 percent is made up of sulfur. These substances--in these proportions--create a powerful chemical reaction when a heat source (usually fire) is introduced. This chemical reaction is the explosion you see with most firecrackers. When the fuse is lit, the fire (or the catalyst) makes its way to the substance wrapped inside the firecracker. The carbon acts as a fuel for the ignition process, while the potassium nitrate (the oxidizer) reacts with the sulfur and carbon. As these substances react, they form nitrogen and carbon dioxide gasses. The substances also react with the external air to create energy. As the reaction occurs, the gasses expand until the wrapper can no longer hold them. When the wrapper bursts, it causes a simultaneous release of energy, making an explosion as well as the cracking sound of the paper breaking.