# The colour of Hydrogen **URL:** \ **Category:** Factual Questions\ **Created:** [March 16, 2010, 2:39pm UTC](https://boards.straightdope.com/t/the-colour-of-hydrogen/532649 "2010-03-16T14:39:17Z")\ **Posts on this page:** 20\ **Page:** 2
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [March 17, 2010, 9:17am UTC](https://boards.straightdope.com/t/the-colour-of-hydrogen/532649/21 "2010-03-17T09:17:19Z")
> [@Imasquare](#): > > I also thought it was due to coloring the surface. I have seen some outdoor pools where the water is green. Not due to algae but because the pool surface is green. I’m not sure what phenomenon you’re describing here - how was the surface coloured? ---
**Author:** ![coremelt](https://avatars.discourse-cdn.com/v4/letter/c/4491bb/32.png) [@coremelt](https://boards.straightdope.com/u/coremelt)\ **Post date:** [March 17, 2010, 9:23am UTC](https://boards.straightdope.com/t/the-colour-of-hydrogen/532649/22 "2010-03-17T09:23:58Z")
> [@Mangetout](#): > > They tried to teach me that too, but I never believed them. I find the persistence of this myth quite remarkable, as the sky is blue for probably less than half the time here in England - so we have abundant opportunity to observe the falsity of the claim. as a native Aussie who lived in UK for 3 years, I never saw a blue ocean there… it was always dirty grey… so the claim may well be true 😉 ---
**Author:** ![Imasquare](https://avatars.discourse-cdn.com/v4/letter/i/5f9b8f/32.png) [@Imasquare](https://boards.straightdope.com/u/Imasquare)\ **Post date:** [March 17, 2010, 9:33am UTC](https://boards.straightdope.com/t/the-colour-of-hydrogen/532649/23 "2010-03-17T09:33:15Z")
> [@Mangetout](#): > > I’m not sure what phenomenon you’re describing here - how was the surface coloured? The floor and walls of the pool are usually blue or green. ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [March 17, 2010, 9:38am UTC](https://boards.straightdope.com/t/the-colour-of-hydrogen/532649/24 "2010-03-17T09:38:34Z")
> [@Imasquare](#): > > The floor and walls of the pool are usually blue or green. Ah, thanks - I thought you meant the surface of the water (and was wondering how you could ever paint it). ---
**Author:** ![Khendrask](https://avatars.discourse-cdn.com/v4/letter/k/3e96dc/32.png) [@Khendrask](https://boards.straightdope.com/u/Khendrask)\ **Post date:** [March 17, 2010, 10:56am UTC](https://boards.straightdope.com/t/the-colour-of-hydrogen/532649/25 "2010-03-17T10:56:05Z")
> [@Mangetout](#): > > Ah, thanks - I thought you meant the surface of the water (and was wondering how you could ever paint it). Freeze it? ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [March 17, 2010, 11:17am UTC](https://boards.straightdope.com/t/the-colour-of-hydrogen/532649/26 "2010-03-17T11:17:28Z")
> [@Khendrask](#): > > Freeze it? Best close the diving board if you’re going to do that. ---
**Author:** ![Cheshire\_Human](https://avatars.discourse-cdn.com/v4/letter/c/5f8ce5/32.png) [@Cheshire\_Human](https://boards.straightdope.com/u/Cheshire_Human)\ **Post date:** [March 17, 2010, 1:21pm UTC](https://boards.straightdope.com/t/the-colour-of-hydrogen/532649/27 "2010-03-17T13:21:37Z")
> [@Mangetout](#): > > Ah, thanks - I thought you meant the surface of the water (and was wondering how you could ever paint it). Oil based paint floating on the water 🙂 Again, close the diving board, you don’t want green people walking around your pool 🙂 ---
**Author:** ![ZenBeam](https://avatars.discourse-cdn.com/v4/letter/z/3ab097/32.png) [@ZenBeam](https://boards.straightdope.com/u/ZenBeam)\ **Post date:** [March 17, 2010, 1:38pm UTC](https://boards.straightdope.com/t/the-colour-of-hydrogen/532649/28 "2010-03-17T13:38:26Z")
> [@Cheshire\_Human](#): > > Again, close the diving board, you don’t want green people walking around your pool 🙂 😕 But it’s St. Patrick’s Day. ---
**Author:** ![billfish678](https://avatars.discourse-cdn.com/v4/letter/b/7bcc69/32.png) [@billfish678](https://boards.straightdope.com/u/billfish678)\ **Post date:** [March 17, 2010, 1:41pm UTC](https://boards.straightdope.com/t/the-colour-of-hydrogen/532649/29 "2010-03-17T13:41:57Z")
> [@Cheshire\_Human](#): > > Again, close the diving board, you don’t want green people walking around your pool 🙂 Thats for sure. Yellow (ahem) and blue make green 🙂 ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [March 17, 2010, 1:48pm UTC](https://boards.straightdope.com/t/the-colour-of-hydrogen/532649/30 "2010-03-17T13:48:37Z")
I went swimming in a public pool once where the water was suddenly deep, murky green one day (we’d been going there nearly every day and it was fine, then it was this impenetrable cloudy green colour). They still let us swim, but for some reason, we never thought to ask why it was like that (or we did, and they didn’t know/tell us - I can’t remember). I think it might be that they filmed something there and had dyed the water to make it look like the sea or a lake (obviously would only work in a cropped shot, with the right lighting etc). ---
**Author:** ![Ruken](https://avatars.discourse-cdn.com/v4/letter/r/f475e1/32.png) [@Ruken](https://boards.straightdope.com/u/Ruken)\ **Post date:** [March 17, 2010, 2:38pm UTC](https://boards.straightdope.com/t/the-colour-of-hydrogen/532649/31 "2010-03-17T14:38:03Z")
> [@Deflagration](#): > > Is it ‘clear’ as in actually colourless or just appears nearly colourless. Note that “clearness” (clarity?) has nothing to do with color, at least when describing liquids. Not so important normally, but keep it in mind before turning in a lab report :). A clear colorless solution and a clear dark red solution are both clear. ---
**Author:** ![ftg](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ftg/32/2801_2.png) [@ftg](https://boards.straightdope.com/u/ftg)\ **Post date:** [March 17, 2010, 4:57pm UTC](https://boards.straightdope.com/t/the-colour-of-hydrogen/532649/32 "2010-03-17T16:57:00Z")
Back in my old Thermo lab days, I saw liquid H, He, N and O. Of these only Oxygen had a noticable color. A beautiful pale blue. In the 1-2 cups range the rest were as colorless as a comparable amount of water. I have no idea what a swimming pool of Hydrogen would look like. ---
**Author:** ![billfish678](https://avatars.discourse-cdn.com/v4/letter/b/7bcc69/32.png) [@billfish678](https://boards.straightdope.com/u/billfish678)\ **Post date:** [March 17, 2010, 5:00pm UTC](https://boards.straightdope.com/t/the-colour-of-hydrogen/532649/33 "2010-03-17T17:00:35Z")
> [@ftg](#): > > Back in my old Thermo lab days, I saw liquid H, He, N and O. Of these only Oxygen had a noticable color. A beautiful pale blue. In the 1-2 cups range the rest were as colorless as a comparable amount of water. I have no idea what a swimming pool of Hydrogen would look like. Could that be due to trace amounts of ozone in the oxygen? IIRC liquid ozone has a rather strong color. ---
**Author:** ![USCDiver](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/uscdiver/32/354_2.png) [@USCDiver](https://boards.straightdope.com/u/USCDiver)\ **Post date:** [March 17, 2010, 6:32pm UTC](https://boards.straightdope.com/t/the-colour-of-hydrogen/532649/34 "2010-03-17T18:32:41Z")
> [@Imasquare](#): > > The floor and walls of the pool are usually blue or green. No they aren’t. Every public/recreational olympic style swimming pool I’ve ever seen (and I’ve seen hundreds) was finished in white. Sometimes it’s white tile, sometimes it’s a thin layer of plaster over the gunite or concrete. ---
**Author:** ![Hypnagogic\_Jerk](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/hypnagogic_jerk/32/4252_2.png) [@Hypnagogic\_Jerk](https://boards.straightdope.com/u/Hypnagogic_Jerk)\ **Post date:** [March 17, 2010, 11:13pm UTC](https://boards.straightdope.com/t/the-colour-of-hydrogen/532649/35 "2010-03-17T23:13:15Z")
> [@billfish678](#): > > Could that be due to trace amounts of ozone in the oxygen? IIRC liquid ozone has a rather strong color. AFAIK liquid oxygen is slightly blue. It’s just its natural colour, I don’t believe it’s due to the presence of ozone. Liquid ozone, as you point out, is deep blue. ---
**Author:** ![billfish678](https://avatars.discourse-cdn.com/v4/letter/b/7bcc69/32.png) [@billfish678](https://boards.straightdope.com/u/billfish678)\ **Post date:** [March 17, 2010, 11:18pm UTC](https://boards.straightdope.com/t/the-colour-of-hydrogen/532649/36 "2010-03-17T23:18:24Z")
> [@USCDiver](#): > > No they aren’t. Every public/recreational olympic style swimming pool I’ve ever seen (and I’ve seen hundreds) was finished in white. Sometimes it’s white tile, sometimes it’s a thin layer of plaster over the gunite or concrete. I think you two are using different life experiences. IME many big/public pools ARE white. OTOH most small private pools ARE NOT white IME. ---
**Author:** ![USCDiver](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/uscdiver/32/354_2.png) [@USCDiver](https://boards.straightdope.com/u/USCDiver)\ **Post date:** [March 17, 2010, 11:23pm UTC](https://boards.straightdope.com/t/the-colour-of-hydrogen/532649/37 "2010-03-17T23:23:52Z")
> [@billfish678](#): > > I think you two are using different life experiences. IME many big/public pools ARE white. OTOH most small private pools ARE NOT white IME. Regardless, the water an indoor Olympic style white bottomed pool still looks blue. So it’s clearly (ha!) not the bottom of the pool or the reflected sky producing that color. ---
**Author:** ![billfish678](https://avatars.discourse-cdn.com/v4/letter/b/7bcc69/32.png) [@billfish678](https://boards.straightdope.com/u/billfish678)\ **Post date:** [March 18, 2010, 12:00am UTC](https://boards.straightdope.com/t/the-colour-of-hydrogen/532649/38 "2010-03-18T00:00:52Z")
> [@Hypnagogic\_Jerk](#): > > AFAIK liquid oxygen is slightly blue. It’s just its natural colour, I don’t believe it’s due to the presence of ozone. Liquid ozone, as you point out, is deep blue. Yes, but here is the way I remember it. You take a bunch of liquid oxygen. You let most of it boil off. What’s left is small amount of deep blue liquid ozone, because ozone boils off at a higher temp. So, it appears in general that run of the mill liquid O2 contains a good fraction of ozone. So is true pure O2 slightly blue, or is it the diluted ozone giving it the blue tint? Just going from memory and pseudo logic here. ---
**Author:** ![Imasquare](https://avatars.discourse-cdn.com/v4/letter/i/5f9b8f/32.png) [@Imasquare](https://boards.straightdope.com/u/Imasquare)\ **Post date:** [March 18, 2010, 12:17am UTC](https://boards.straightdope.com/t/the-colour-of-hydrogen/532649/39 "2010-03-18T00:17:05Z")
> [@USCDiver](#): > > Regardless, the water an indoor Olympic style white bottomed pool still looks blue. So it’s clearly (ha!) not the bottom of the pool or the reflected sky producing that color. So water must have a blue tint then. That’s something I didn’t know after 48 years of life. ---
**Author:** ![markci](https://avatars.discourse-cdn.com/v4/letter/m/8491ac/32.png) [@markci](https://boards.straightdope.com/u/markci)\ **Post date:** [March 18, 2010, 1:57am UTC](https://boards.straightdope.com/t/the-colour-of-hydrogen/532649/40 "2010-03-18T01:57:36Z")
> [@Imasquare](#): > > So water must have a blue tint then. That’s something I didn’t know after 48 years of life. I guess you don’t get out of the house much? [Previous page](https://boards.straightdope.com/t/the-colour-of-hydrogen/532649.md?page=1) [Next page](https://boards.straightdope.com/t/the-colour-of-hydrogen/532649.md?page=3)