Speaker 1: Welcome to brain Stuff, a production of iHeart Radio. Hey
Speaker 1: brain Stuff. Lauren voc Obam here with another classic episode
Speaker 1: from our former host, Christian Sagar. With Halloween coming up
Speaker 1: and families preparing to engage in the safest possible trigger treating,
Speaker 1: I was thinking about a more traditional piece of trigger
Speaker 1: treat safety gear, the glow stick, and this one, Christian
Speaker 1: breaks down how they work. Hey brain stuff, this is
Speaker 1: Christian Sager. You have seen glow sticks before. I bet
Speaker 1: they bring a festive glow to Halloween, trick or treating
Speaker 1: and New Year's Eve celebrations. And they are a useful
Speaker 1: gear for explorers, from scuba divers to spelunkers. When you
Speaker 1: find a bunch of people gathered at a party in
Speaker 1: the dark, at least a few of them will probably
Speaker 1: be wielding glow sticks. But what the heck are these
Speaker 1: things and how do they work? Well? Glow sticks are
Speaker 1: powered by a process called kemma luminescence. Don't let the
Speaker 1: name scare you. Luminescence is just a fancy word for
Speaker 1: any emission of light not caused by heating. We see
Speaker 1: luminescence and stuff like TVs, neon signs and fireflies. The
Speaker 1: chemo Luminescence in glow sticks is a pretty simple reaction
Speaker 1: caused by mixing chemical compounds. Compounds are made up of
Speaker 1: different elements bonded together in specific proportions so that they
Speaker 1: can't be mechanically separated. It takes a chemical reaction to
Speaker 1: sort out, for example, the oxygen from the hydrogen in water.
Speaker 1: When you mix a compound with other stuff, you can
Speaker 1: set off that reaction, and as the atoms rearrange themselves,
Speaker 1: they'll either absorb or release energy. If you look inside
Speaker 1: a glow stick, you'll see that there's a small glass
Speaker 1: vial in the tube. This file typically contains a hydrogen
Speaker 1: peroxide solution called the activator. It's floating in a solution
Speaker 1: containing a compound called phenol oxalate ester and a fluorescent dye.
Speaker 1: You still with me, Okay. When you snap a glow stick,
Speaker 1: the vile brakes and the hydrogen peroxide reacts with the
Speaker 1: phenyl oxalate ester, creating two other compounds, phenol and a
Speaker 1: paraoxy acid esther Okay, still with me again? Okay. This
Speaker 1: para oxy acid stuff is unstable, so it decomposes and
Speaker 1: produces additional phenol. It also produces a cyclic perioxy compound,
Speaker 1: which decomposes to carbon dioxide. This decomposition releases energy to
Speaker 1: the dye. The electrons in the dyes atoms jump to
Speaker 1: a higher level than fall back down, releasing energy in
Speaker 1: the form of light. The other chemicals in the fluorescent
Speaker 1: dye determine the color of this light. All this happens
Speaker 1: within moments of snapping and shaking your glow stick. Depending
Speaker 1: on which compounds are used, the chemical reaction can continue
Speaker 1: for anywhere from just a few minutes to hours. Warmer
Speaker 1: temperatures will accelerate the reaction, making the stick glow brighter,
Speaker 1: but for a shorter amount of time. When it's cooler,
Speaker 1: the reaction will slow down, making the light dimmer, which
Speaker 1: means that if you want to preserve your light stick,
Speaker 1: put it in the freezer overnight. It won't stop the process,
Speaker 1: but it will slow it down and drag out the reaction.
Speaker 1: So it turns out that there's some pretty nifty science
Speaker 1: behind the humble glow stick. Check it out the next
Speaker 1: time you're scuba diving, partying, or you know, whatever it
Speaker 1: is you do in the dark. Today's episode was written
Speaker 1: by Ben Bolin and produced by Tyler clang. For more
Speaker 1: on this and lots of other glowing topics, visit how
Speaker 1: stuff works dot com. Brain Stuff is production of iHeart
Speaker 1: Radio or more podcasts my heart Radio, visit the iHeart
Speaker 1: Radio app, Apple Podcasts, or wherever you listen to your
Speaker 1: favorite shows.