Speaker 1: Welcome to brain Stuff from How Stuff Works. Hi, I'm
Speaker 1: Christian Sager. This is brain stuff And today's question is
Speaker 1: what is silica gel? And why do I find little
Speaker 1: packets of it in so many things? I mean, that's weird, right,
Speaker 1: Why would my new boots and my beef jerky be
Speaker 1: packed with the same stuff. Silica or more precisely, silicon
Speaker 1: dioxide is the same stuff that quartz in sand are
Speaker 1: made of. It's a desiccant, meaning it adds orbs and
Speaker 1: holds water vapor. And that's ads orbs with an ad
Speaker 1: not absorbs. When we say that something ads orbs moisture,
Speaker 1: we mean that water molecules adhere to the surface of
Speaker 1: the material. Think of the way that sand can seem
Speaker 1: to soak up water. The water is really just adhering
Speaker 1: to each grain. Basically, silica gel does the same thing.
Speaker 1: It's covered in millions of tiny pores that can retain moisture.
Speaker 1: It can actually adds orb about forty of its weight
Speaker 1: in moisture and can thus reduce the relative humidity in
Speaker 1: a closed container down to around So you'll find silica
Speaker 1: gel packs and anything that would be affected by excess moisture.
Speaker 1: It's in with leather products, where it can limit the
Speaker 1: growth of mold. You'll see it packaged with electronics to
Speaker 1: reduce condensation, and because silica gel is nearly harmless, you'll
Speaker 1: find it preventing spoilage in foods like pepperoni. You still
Speaker 1: don't want to eat it, though. If you emptied out
Speaker 1: a packet and ate the beads, they would begin adsorbing
Speaker 1: moisture from your tongue, gums, and the rest of your mouth.
Speaker 1: Your first instinct would probably be to spit it out.
Speaker 1: But if you did swallow it, well, okay, probably you'd
Speaker 1: be fine. But not all silica gel is the same.
Speaker 1: Some has a toxic coating of cobalt chloride. Swallowing this
Speaker 1: stuff probably won't kill you, but it might cause nausea, vomiting,
Speaker 1: and a few other less than awesome symptoms. And when
Speaker 1: it comes to keeping things dry, silica gel works pretty well,
Speaker 1: which is why it's so widespread. It's also found in
Speaker 1: vitamin containers, industrial air systems, and oddly enough, containers of
Speaker 1: cat litter. And this stuff is reusable. You can dry
Speaker 1: it out by heating it in an oven at about
Speaker 1: three hundred degrees fahrenheit. That's about one fifty degrees celsius,
Speaker 1: and people have found all sorts of ways to reuse it.
Speaker 1: There might be too many to list. I mean, all right,
Speaker 1: I guess I can try. Here. It goes protecting papers
Speaker 1: from humidity, drying flowers, preventing rust on tools, preventing condensation
Speaker 1: on windows and inside picture frames, preserving art in display cases,
Speaker 1: mitigating small spills in luggage, slowing silver tarnishing, stopping seed mold,
Speaker 1: and preventing camera lens from fog. Check out the brain
Speaker 1: stuff channel on YouTube, and for more on this and
Speaker 1: thousands of other topics, visit how stuff works dot com