Darker colors absorb more light than lighter colors. Light is favorable for the decomposition of hydrogen peroxide. Then shouldn't it be that the chemical is stored in white or lighter colored bottles, which reflect all the light?
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1$\begingroup$ Hydrogen peroxide decomposes in presence of light especially from the UV rays. Dark bottles filters the UV rays. Similar to chloroform: chemistry.stackexchange.com/questions/57788/… $\endgroup$Nilay Ghosh– Nilay Ghosh2024-06-11 04:17:47 +00:00Commented Jun 11, 2024 at 4:17
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1$\begingroup$ H2O2 is sure kept in white plastic, afaik. $\endgroup$Mithoron– Mithoron2024-06-11 11:17:29 +00:00Commented Jun 11, 2024 at 11:17
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True white reflects "all" light, but most plastic bottles that look white actually are translucent, reflecting and scattering some light, but transmitting quite a bit, too. Lining a bottle with aluminum foil, as commonly done for some food containers, would make it truly reflective... but would raise the cost, and any aluminum in contact with $\ce{H2O2}$ decomposes it.
Try a simple experiment: cut a piece of plastic from a white milk carton, and place a light behind it. A substantial amount shows through.
True black absorbs "all" light, and would protect $\ce{H2O2}$, and some peroxide bottles are opaque black. However, blue and ultraviolet are the colors active in decomposing $\ce{H2O2}$, and dark brown serves about as well as black.
As to the particular choice of what color bottle to use, cost might be the primary factor, and tradition of selling $\ce{H2O2}$ in brown glass bottles might play a secondary role. Inexpensive iron, titanium and other compounds are used to make brown bottles. And there are 99 bottles or more colored brown.
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1$\begingroup$ Amber glass for typical chemicals does not come from adding titanium. It comes from iron/sulfur/carbon combination. $\endgroup$ACR– ACR2024-06-11 05:20:25 +00:00Commented Jun 11, 2024 at 5:20
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$\begingroup$ @AChem, yes, corrected. Though I got the Ti from Wikipedia, I should have remembered that iron compounds have always been a problem in getting clear glass (making it greenish as well as brown, depending on oxidation state). $\endgroup$DrMoishe Pippik– DrMoishe Pippik2024-06-11 13:17:43 +00:00Commented Jun 11, 2024 at 13:17