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Speaker 1: Welcome to brain Stuff, a production of iHeart Radio. Hey

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Speaker 1: brain Stuff, Lauren Vogo bomb here with a classic podcast

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Speaker 1: episode for you. This one turns to chemistry and history

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Speaker 1: to answer and everyday question. Why are hydrogen peroxide bottles opaque?

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Speaker 1: Brown of all colors? Hey brain Stuff, Lauren Vogo bomb here.

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Speaker 1: What do you get when you combine two molecules of

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Speaker 1: hydrogen and two molecules of oxygen? Well, you get H

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Speaker 1: two O two. More commonly known as hydrogen peroxide. Used

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Speaker 1: in all kinds of industries from food processing to papermaking,

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Speaker 1: two textiles to electronics, peroxide is a great disaffecting and

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Speaker 1: bleaching agent. It's clear and colorless, and when poured over

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Speaker 1: an open wound, peroxide will kill many types of microorganisms.

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Speaker 1: It's also an extremely stable compound when properly stored, which

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Speaker 1: is why when you buy hydrogen peroxide it usually comes

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Speaker 1: in a brown plastic bottle. Here's why. Many semical compounds

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Speaker 1: break down over time, and hydrogen peroxide is no exception.

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Speaker 1: Although it is extremely stable, the solution can start to

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Speaker 1: decompose when it comes in contact with light and heat.

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Speaker 1: The brown bottle in your medicine cabinet is a bulwark

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Speaker 1: against those two catalysts. Light cannot penetrate the tint of

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Speaker 1: the brown bottle, preventing oxidation, which you want to prevent

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Speaker 1: because it can result in an increase in temperature. As

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Speaker 1: peroxide breaks down, it gets hotter. As a result, the

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Speaker 1: compounds decomposition rate accelerates. In fact, for every ten degree

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Speaker 1: fahrenheit rise in temperature, the decomposition rate nearly doubles, meaning

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Speaker 1: that around seventy two degrees fahrenheit that's about twenty two celsius,

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Speaker 1: it decomposes at a rate of one percent per year.

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Speaker 1: But if it got up to one fifty one degrees

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Speaker 1: fahrenheit that's about sixty six celsius, it would be decomposing

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Speaker 1: at a rate of one percent per week. By the

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Speaker 1: time it hit the boiling point of water, it would

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Speaker 1: be going at nearly two percent per day. Moreover, some

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Speaker 1: sort of contaminants such as dust, silver, lead, or another metal,

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Speaker 1: gets into the solution, it can spark a fire. Although

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Speaker 1: the solution itself is not explosive, those in the industry

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Speaker 1: must handle hydrogen peroxide with care. If the solution is

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Speaker 1: in a closed system, such as a storage tank and

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Speaker 1: it starts to break down, pressure can build up, causing

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Speaker 1: the tank or a pipe or line to rupture. The

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Speaker 1: good news is that the bottle of peroxide in your

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Speaker 1: medicine cabinet only contains about a three solution, far less

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Speaker 1: than that the food industry uses. For example. You may

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Speaker 1: also notice the peroxide never comes in a clear glass container.

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Speaker 1: That's because glass bottles may contain dissolved alkali metal ions

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Speaker 1: that can react with the solution. Today's episode is based

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Speaker 1: on the article why does hydrogen peroxide come in a

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Speaker 1: brown bottle? On how supworks dot com written by John Parentano.

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Speaker 1: Brain Stuff is production of I Heart Radio in partnership

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Speaker 1: with how stuff works dot Com and as produced by

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Speaker 1: Tyler Crying and Ramsey. Out four more podcasts from my

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Speaker 1: heart Radio, Visit the i heart Radio app, Apple Podcasts,

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Speaker 1: or wherever you listen to your favorite show. H