Sulfur has this magical property that when you mix it with potassium nitrate, it can lower the activation energy significantly.So what you need is a mixture of potassium nitrate, charcoal and sulfur.And that is the recipe for gunpowder.

I cannot believe the precision of that huge camera on there. Gene is going to try to fly the FPV drone through fireworks as they explode. He makes the channel called Potato Jet and does tech reviews as well as filmic stuff.

The first recorded instance of something like a firework occurred in China over 2000 years ago. People would get a piece of bamboo with the ends closed and throw it in a fire. This evolved into black powder with the addition of potassium nitrate, sulfur and honey.

When heated, the mixture of potassium nitrate, charcoal and sulfur creates gunpowder. This has a high activation energy, but with sulfur, the energy is significantly lowered and the reaction becomes explosive.

This video was sponsored by KiwiCo. More about them at the end of the show. Mr. Beast has got nothing on this - this is the biggest, hottest and most explosive video on fireworks ever, covering everything from the invention of gunpowder to how fire can burn underwater, how fireworks are made, the colors, shapes, fuses and how they’re launched. We’ll even see what it’s like to fly through fireworks. And then you add a fuse.And then you can prime it with gunpowder.It’s a very simple process.

Sulfur starts reacting with the other ingredients at lower temperatures, giving off heat and acting like kindling. The classic gunpowder recipe is 75% potassium nitrate, 10% sulfur, and 15% charcoal. To test the reaction, a meter of homemade gunpowder was lit. It took a long time to burn due to the large granules of charcoal and potassium nitrate. To compare, store bought gunpowder was used. The reaction is complicated, but produces a lot of smoke due to the formation of solids. To increase the reaction, the gunpowder was confined in a tube and a bigger bang was produced. To get an even bigger bang, 20 grams of black powder was used. Fireworks are made of a shell with gunpowder inside, reinforced with cardboard and paper mache. The shell is primed with gunpowder and a fuse is added. And I was like, yeah, right, like that’s gonna happen.But when I actually saw the quick match in action, I was like, oh, okay, this is actually gonna work.And it did.(all laughing) - Wow.

Wow! The size of fireworks typically seen on a 4th of July display range from two and a half inch up to five inch. Larger sizes such as six inch and above are usually found in locations with large properties, such as desert shoot sites or barges. On special occasions, fireworks can even reach sizes of 12 inch, 16 inch and bigger. The biggest aerial firework ever was a whopping 1.44 meters wide and weighed the same as a car!

To launch a firework into the air, black powder is used. A typical shell contains a baggie of black powder underneath it, which fires the shell up to 800 feet in the air. For larger shells such as 16 inch, pounds of black powder are used and placed in a big plastic tube called a mortar. The pyro technician gets two bangs for every one the audience does; one when the mortar fires and another when the shell explodes.

When the shell explodes, the internal contents burn up before it reaches the ground. The casing will come down in pieces, which is why a fallout zone or exclusion zone is set up for the pyro crew. Malfunctions are rare, but it does happen.

To ensure the shell goes straight up, the simplest fuse consists of cotton string soaked in black powder and allowed to dry out. This is known as black match and it burns two to three seconds an inch. When encased in craft paper, the burn rate increases from a couple seconds an inch to anywhere from 30 to a hundred feet a second. This is how the finale is shot so fast.

It’s amazing that fireworks can be so big and powerful! I’m going to light this small black match and try to race the signal to the other end. But I was not prepared for what happened next. Suspenseful music Explosions popping Ah! Jesus, what the heck was that? Suspenseful music Explosions popping You are kidding me. You didn’t tell me it was gonna do that. The force of the combustion products causes the quick match to whip around wildly. It’s incredible how much the paper containing the reagents and heat accelerates the reaction. Explosion pops Ah! Man. Every time, every time that gets me. One problem with these basic fuses is that they aren’t waterproof. Even though they contain the fuel and oxidizer, they need heat and water is too good at conducting the heat away from the fuse, thus snuffing out the reaction. I thought that since the flame comes out with such high pressure, it might be able to stay lit underwater. Water splashes And it did for a while, but eventually the water got in there and stole the heat. So I think that the water is putting it out by pulling the heat away from it, not having enough energy to keep burning. Water burbling There are special flares made for underwater applications, but even those have similar problems. Water burbling You can see the gaseous combustion products being released and bubbling to the surface. While this flare lasted longer, the water still eventually put it out. Water burbling Very big firework store. Cheerful music I feel like we have to get this, spins? Fireworks popping And it’s… Water burbling Fuses are not only used to light fireworks, they are a core component inside a firework. The quick match flashes really quick down into the black powder lift that ignites and, while it’s pushing the shell out of the mortar, it lights the time fuse. This is what would actually be in the shell to give you the time delay from the time the lift charge fires to the time the shell hits apogee and explodes in the sky. It’s typically lacquer coated and these fuses are typically waterproof. Explosion popping Whoa! Water burbling Wow! Both laugh Water burbling It’s really important that the time delay fuse keeps the combustion contained inside it so the firework only explodes when you want it to, at the very peak of its trajectory. We tested it underwater and it worked. Water burbling So it has a powder core with a fiber wrap to it and is lacquer coated. You can see the gaseous combustion products being released and bubbling to the surface. Water burbling That was impressive. Both of us laughed when we talked about the science behind fireworks. Rice hulls are used to create a granular powder, which is then coated with black powder to create a peony shell - a traditional firework. It’s interesting to think that when you see a firework go off, all the little points of light are actually about that size. We then discussed the speed of the drone and how it’s tricky to fly it in the dark. Finally, we talked about the colors of fireworks and how they are created through quantum mechanics. Copper ions absorb energy from the combustion and when they drop back down to a lower energy level, they give off a blue light predominantly. It’s a thing of beauty! The colors come from the different elements used, like copper, calcium, and barium.The explosions are triggered by electric matches, and the sound is just the combustion of the fuel and the oxidizer.The patterns are created by arranging the stars in the shell.The result is an awe-inspiring display of light and sound that can be seen and heard from miles away. Every time a KiwiCo crate shows up at our house, my kids get really excited. The purpose of these crates is to provide hands-on projects that teach about science, technology, engineering, and design, while also being fun. Each month, KiwiCo delivers a crate right to your door with everything you need to complete the project. With nine different product lines targeted at different age groups, KiwiCo is a great way to grow with your kids.

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