You may have seen a certain candle relighting hack on TikTok. In one video on the platform, TikTok user Jacob Feldman demonstrates what will surely become your next dinner party trick. “This is how you relight the candle using smoke,” he says, before blowing out a candle, holding a lit lighter up to the resulting smoke, and relighting the candle below.
“As a matter of fact, it traces the path of the smoke,” Jacob says in the 18-second clip.
It’s like magic, right? But there’s actually science behind the trick.
The candle relight hack you see on TikTok actually ignites vaporized wax.
As science writer and chemistry expert Anne Marie Helmenstine, Ph.D., explains for ThoughtCo, you’re not igniting the smoke when you do this trick. Instead, you’re reigniting vaporized wax that’s generated by the heat of the candle flame.
“When you blow the candle out, vaporized wax briefly remains in the air. If you apply a heat source quickly enough, you can ignite the wax and use that reaction to relight the wick of the candle,” Anne writes. “Although it looks like you’re lighting the candle with smoke, it’s really just the wax vapor that ignites. Soot and other debris from the flame aren’t ignited.”
TikTok users are duly impressed.
“THAT WAS ACTUALLY SO COOL OMG” another person wrote in all-caps excitement.
“SORCERY,” a third user said.
Somebody else, meanwhile, joked that PBS just called for Jacob. “They are ready to throw money at you to host a children’s show,” that commenter said.
Even the official TikTok account for the L.A. Galaxy soccer team got in on the comments, calling Jacob’s trick “terrifying.”
One person, though, put a wet blanket on this fiery spectacle. “Why would I [blow] the candle out just to light it again two seconds later?” that skeptic wrote.
You can also see the candle-relighting trick at 2,500 frames a second.
In a 2015 YouTube video, Gavin Free and Daniel Gruchy of the Slo Mo Guys channel did the same candle-relighting trick but filmed it with a Vision Research Phantom high-speed camera, capturing the action at 2,500 frames per second.
“So what’s actually happening is, the wax of the candle is being burnt and vaporized,” Daniel says, sounding off on the science in the video. “And what you’re actually doing is relighting the vapor trail of the material, the wax, and it’s tracing it back down into the candle wick and relighting it.”
As the National Candle Association explains, waxes are hydrocarbons made from hydrogen and carbon. When you light a candle, the heat from the lighter’s flame melts the wax, and that liquid wax then travels up the wick, where the lighter’s flame breaks the hardrocaxrbons down into molecules of hydrogen and carbon. “These vaporized molecules are drawn up into the flame, where they react with oxygen from the air to create heat, light, water vapor, and carbon dioxide.”
The more you know, right?