The Science of Sparklers

(light, playful music)

[Voiceover] There's a lot of chemistry in physics that

goes into the sparklers you'll be waving around

on the fourth of July.

But the glowing part of the

sparkler comes from just one ingredient,

a metal powder that heats until it's incandescent.

And they burn a crazy hot 1800 to 3000 degrees.

There are two reasons the sparks don't burn when

they hit your skin, thermal energy and size.

Those insanely high temperatures aren't a problem,

because as the sparks fly through the air,

they cool off really quickly.

That's thanks to their tiny size and high surface area.

The more of the spark that's exposed to the air,

the faster it'll cool off.

But, be careful with all fireworks, and never touch

the burning portion of the sparkler.

(light, playful music)