# Does this look real (science) or is it fake? **URL:** \ **Category:** Factual Questions\ **Created:** [February 4, 2008, 5:00pm UTC](https://boards.straightdope.com/t/does-this-look-real-science-or-is-it-fake/436223 "2008-02-04T17:00:49Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![Scipro8](https://avatars.discourse-cdn.com/v4/letter/s/ebca7d/32.png) [@Scipro8](https://boards.straightdope.com/u/Scipro8)\ **Post date:** [February 4, 2008, 5:00pm UTC](https://boards.straightdope.com/t/does-this-look-real-science-or-is-it-fake/436223/1 "2008-02-04T17:00:49Z")
I find science confusing and with the things you can do with photoshop I don’t know what to believe or not. Can you really float a boat like this in mid air? Or is it just a trick? Also the voices seem faked. [![](https://img.youtube.com/vi/XjCmwuGKR6g/hqdefault.jpg "Magic Floating Boat - Sulfur Hexafluoride") ](https://www.youtube.com/watch?v=XjCmwuGKR6g) Thanks ---
**Author:** ![glee](https://avatars.discourse-cdn.com/v4/letter/g/b5a626/32.png) [@glee](https://boards.straightdope.com/u/glee)\ **Post date:** [February 4, 2008, 5:11pm UTC](https://boards.straightdope.com/t/does-this-look-real-science-or-is-it-fake/436223/2 "2008-02-04T17:11:21Z")
[QUOTE=Scipro8] I find science confusing and with the things you can do with photoshop I don’t know what to believe or not. Can you really float a boat like this in mid air? Or is it just a trick? Also the voices seem faked. [![](https://i.ytimg.com/vi/XjCmwuGKR6g/hqdefault.jpg "Magic Floating Boat - Sulfur Hexafluoride") ](https://www.youtube.com/watch?v=XjCmwuGKR6g) Thanks [/QUOTE] Welocme to the SDMB. 🙂 First, it’s not a boat, it’s some aluminium foil! Helium is lighter than air, which is why balloons filled with helium float upwards. Since aluminium foil is pretty light too, there’s no reason it won’t float. I have a helium balloon with a radio receiver and a twin fan motors attached. The helium has enough upthrust to lift everything, and you can steer the balloon by using either or both of the fans. 🆒 ---
**Author:** ![beowulff](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beowulff/32/542_2.png) [@beowulff](https://boards.straightdope.com/u/beowulff)\ **Post date:** [February 4, 2008, 5:11pm UTC](https://boards.straightdope.com/t/does-this-look-real-science-or-is-it-fake/436223/3 "2008-02-04T17:11:32Z")
Absolutely possible. ---
**Author:** ![Scipro8](https://avatars.discourse-cdn.com/v4/letter/s/ebca7d/32.png) [@Scipro8](https://boards.straightdope.com/u/Scipro8)\ **Post date:** [February 4, 2008, 5:15pm UTC](https://boards.straightdope.com/t/does-this-look-real-science-or-is-it-fake/436223/4 "2008-02-04T17:15:59Z")
[QUOTE=glee] Welocme to the SDMB. 🙂 First, it’s not a boat, it’s some aluminium foil! Helium is lighter than air, which is why balloons filled with helium float upwards. Since aluminium foil is pretty light too, there’s no reason it won’t float. I have a helium balloon with a radio receiver and a twin fan motors attached. The helium has enough upthrust to lift everything, and you can steer the balloon by using either or both of the fans. 🆒 [/QUOTE] Yea sure I understand the heluim but what about the other stuff is it really sooo heavy that air floats on it??? How is that possible? ---
**Author:** ![pulykamell](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pulykamell/32/3166_2.png) [@pulykamell](https://boards.straightdope.com/u/pulykamell)\ **Post date:** [February 4, 2008, 5:16pm UTC](https://boards.straightdope.com/t/does-this-look-real-science-or-is-it-fake/436223/5 "2008-02-04T17:16:56Z")
[QUOTE=glee] Welocme to the SDMB. 🙂 First, it’s not a boat, it’s some aluminium foil! Helium is lighter than air, which is why balloons filled with helium float upwards. Since aluminium foil is pretty light too, there’s no reason it won’t float. I have a helium balloon with a radio receiver and a twin fan motors attached. The helium has enough upthrust to lift everything, and you can steer the balloon by using either or both of the fans. 🆒 [/QUOTE] Forgive me if I’m misunderstanding you, but they’re floating it not on the helium, but the sulphur hexafluoride, which is heavier than air. Otherwise, the helium would have escaped the tank. As it is, the sulphur hexafluoride (which is 5 times as dense as air), is contained in the fish tank, and is dense enough to support the weight of aluminum foil [Another video here.](http://www.youtube.com/watch?v=1PJTq2xQiQ0) ---
**Author:** ![cmyk](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cmyk/32/3353_2.png) [@cmyk](https://boards.straightdope.com/u/cmyk)\ **Post date:** [February 4, 2008, 5:21pm UTC](https://boards.straightdope.com/t/does-this-look-real-science-or-is-it-fake/436223/6 "2008-02-04T17:21:36Z")
It’s all about density. The Sulfer Hexaflouride is denser than air, so it’s contained in the aquarium and can’t roll out of it. Think of it as the opposite of Helium. As for the voices… never did [whippits](http://en.wikipedia.org/wiki/Legal_intoxicants#Inhalants), huh? 😉 ---
**Author:** ![WhyNot](https://avatars.discourse-cdn.com/v4/letter/w/c77e96/32.png) [@WhyNot](https://boards.straightdope.com/u/WhyNot)\ **Post date:** [February 4, 2008, 5:22pm UTC](https://boards.straightdope.com/t/does-this-look-real-science-or-is-it-fake/436223/7 "2008-02-04T17:22:23Z")
Absolutely real. [Sulfur hexafuoride](http://en.wikipedia.org/wiki/Sulfur_hexafluoride) can be thought of as the “opposite” of helium in some ways, which the girls illustrate in their video. It’s denser than room air, where helium is lighter than room air. It makes your voice deeper, instead of higher, and it pushes things down instead of lifting them up! It’s really cool stuff to play with, and it’s pretty safe. [Rosie and Anna have a website](http://rosieandanna.com/) with other fun videos, too. Some science, some crafts; it’s pretty neat! ---
**Author:** ![pulykamell](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pulykamell/32/3166_2.png) [@pulykamell](https://boards.straightdope.com/u/pulykamell)\ **Post date:** [February 4, 2008, 5:23pm UTC](https://boards.straightdope.com/t/does-this-look-real-science-or-is-it-fake/436223/8 "2008-02-04T17:23:34Z")
[And here’s a video demonstrating what happens when you breath SF6 and try to talk.](http://wm.kusa.gannett.edgestreams.net/news/1152575853563-07-10-06-spangler-4p1.wmv) ---
**Author:** ![glee](https://avatars.discourse-cdn.com/v4/letter/g/b5a626/32.png) [@glee](https://boards.straightdope.com/u/glee)\ **Post date:** [February 4, 2008, 5:23pm UTC](https://boards.straightdope.com/t/does-this-look-real-science-or-is-it-fake/436223/9 "2008-02-04T17:23:48Z")
[QUOTE=pulykamell] Forgive me if I’m misunderstanding you, but they’re floating it not on the helium, but the sulphur hexafluoride, which is heavier than air. Otherwise, the helium would have escaped the tank. As it is, the sulphur hexafluoride (which is 5 times as dense as air), is contained in the fish tank, and is dense enough to support the weight of aluminum foil [Another video here.](http://www.youtube.com/watch?v=1PJTq2xQiQ0) [/QUOTE] You’re quite correct. 🙂 I wasn’t sure how much science Scipro8 could take, so started with the helium, since that was mentioned and shown in the video first. ---
**Author:** ![Squink](https://avatars.discourse-cdn.com/v4/letter/s/b5e925/32.png) [@Squink](https://boards.straightdope.com/u/Squink)\ **Post date:** [February 4, 2008, 5:30pm UTC](https://boards.straightdope.com/t/does-this-look-real-science-or-is-it-fake/436223/10 "2008-02-04T17:30:13Z")
[Sulfur hexafluoride](http://en.wikipedia.org/wiki/Sulfur_hexafluoride) has a density of about 0.006164 g / cc at atmospheric pressure and temperature. A 1 square foot (300 mm) piece of aluminum foil, about 0.03mm thick, has a volume of 2.7 cc, so masses (density = 2.7) about 7.3 g In order to float, that 7.3 grams would have to displace 1.18 liters of gas. That’d require a boat about 12cm long, wide and tall. That’s doable with a 30 X 30 cm piece of foil. ---
**Author:** ![Szlater](https://avatars.discourse-cdn.com/v4/letter/s/90ced4/32.png) [@Szlater](https://boards.straightdope.com/u/Szlater)\ **Post date:** [February 4, 2008, 5:37pm UTC](https://boards.straightdope.com/t/does-this-look-real-science-or-is-it-fake/436223/11 "2008-02-04T17:37:54Z")
[QUOTE=WhyNot] It makes your voice deeper, instead of higher, and it pushes things down instead of lifting them up! It’s really cool stuff to play with, and it’s pretty safe. [/QUOTE] It can be safely handled, but it isn’t “safe”… it displaces atmosphere, and can pool in low areas and so poses the same hazards as other lab gases, such as nitrogen and carbon dioxide. I’m always dubious of people who let anyone, especially kids, inhale stuff in labs. Far too easy to have a tragic accident. Also, it’s a total disregard for the basic lab safety that teachers are supposed to drum into kids. It’s one of the things that really annoys me about Mythbusters, especially when Adam takes Helium straight from the tank. Not having a go at you. I’ve just been in labs where poor safety caused real injuries amongst people who should have known better. ---
**Author:** ![Tyrrell\_McAllister](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tyrrell_mcallister/32/16772_2.png) [@Tyrrell\_McAllister](https://boards.straightdope.com/u/Tyrrell_McAllister)\ **Post date:** [February 4, 2008, 7:03pm UTC](https://boards.straightdope.com/t/does-this-look-real-science-or-is-it-fake/436223/12 "2008-02-04T19:03:00Z")
And all that roughhousing was atrocious! They should at least have been wearing helmets ;). ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [February 5, 2008, 12:20am UTC](https://boards.straightdope.com/t/does-this-look-real-science-or-is-it-fake/436223/13 "2008-02-05T00:20:32Z")
> [@](#): > > I’m always dubious of people who let anyone, especially kids, inhale stuff in labs. I had the same reaction. Helium is safe enough to inhale, since it’ll escape from your lungs on its own quickly enough. But sulfur hexafluoride will just stay in your lungs, so you have to do a handstand afterwards to get rid of it. It can be done safely, but I wouldn’t let children do it. Back on topic, it should be noted that any gas will gradually diffuse out of an open container, even if it is heavier than air. That’s why they had a cover over the bucket before they used it, and why there was a hose in the big fish tank (to continually replenish it). ---
**Author:** ![pulykamell](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pulykamell/32/3166_2.png) [@pulykamell](https://boards.straightdope.com/u/pulykamell)\ **Post date:** [February 5, 2008, 1:48am UTC](https://boards.straightdope.com/t/does-this-look-real-science-or-is-it-fake/436223/14 "2008-02-05T01:48:01Z")
[QUOTE=Chronos] But sulfur hexafluoride will just stay in your lungs, so you have to do a handstand afterwards to get rid of it. [/QUOTE] [That’s not what this MD says.](http://yarchive.net/med/helium_breathe.html) > [@](#): > > The forces of mixing caused by gas > inhalation and exhalation in normal lungs are HUGE. More than enough > to stir up any mix of mere gases, even when one is 5 times heavier than > air, as in SF6. Heck, I’ve done fluoroscopy of living dogs being > ventilated with oxygen while their lungs were full of _liquid > fluorocarbon,_ which has twice the density of water, and several > thousand times the density of air. The mixing is still excellent, and > the bubble jets get all the way to the ends of the airways with every > breath (and the dogs are fine). An inert gas like xenon will simply be > mixed up and purged in a breath or two (xenon has been successfully > used as a gas anaesthetic). ---
**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:** [February 5, 2008, 1:53am UTC](https://boards.straightdope.com/t/does-this-look-real-science-or-is-it-fake/436223/15 "2008-02-05T01:53:43Z")
Yeah, I think the lungs are a sufficiently turbulent system to be able to expel denser gases along with the air. I’m just amazed that something called sulphur hexafluoride isn’t horribly toxic- it sounds like it ought to be. ---
**Author:** ![WarmNPrickly](https://avatars.discourse-cdn.com/v4/letter/w/d78d45/32.png) [@WarmNPrickly](https://boards.straightdope.com/u/WarmNPrickly)\ **Post date:** [February 5, 2008, 2:10am UTC](https://boards.straightdope.com/t/does-this-look-real-science-or-is-it-fake/436223/16 "2008-02-05T02:10:32Z")
[Here](http://youtube.com/watch?v=vcVMjGRzDz8&feature=related) is another great effect of sulfur hexafluoride. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [February 5, 2008, 9:52pm UTC](https://boards.straightdope.com/t/does-this-look-real-science-or-is-it-fake/436223/17 "2008-02-05T21:52:19Z")
> [@](#): > > I’m just amazed that something called sulphur hexafluoride isn’t horribly toxic- it sounds like it ought to be. Sulfur and fluorine are both toxic more or less because they both really like to react with things. Put them together, and they both take the opportunity to react to a very great degree, until they turn into something (SF[sub]6[/sub]) which is about as reacted as it can get. So it can’t react any more. **pulykamel** , I won’t dispute that MD’s word. But I likewise won’t go huffing any SF[sub]6[/sub], if it’s all right with him. ---
**Author:** ![Lemur866](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lemur866/32/434_2.png) [@Lemur866](https://boards.straightdope.com/u/Lemur866)\ **Post date:** [February 5, 2008, 9:59pm UTC](https://boards.straightdope.com/t/does-this-look-real-science-or-is-it-fake/436223/18 "2008-02-05T21:59:00Z")
[QUOTE=Chronos] Sulfur and fluorine are both toxic more or less because they both really like to react with things. Put them together, and they both take the opportunity to react to a very great degree, until they turn into something (SF[sub]6[/sub]) which is about as reacted as it can get. So it can’t react any more. [/QUOTE] And that’s why horribly reactive toxic sodium and horribly reactive toxic chlorine are edible when reacted together. ---
**Author:** ![Musicat](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/musicat/32/20189_2.png) [@Musicat](https://boards.straightdope.com/u/Musicat)\ **Post date:** [February 5, 2008, 10:09pm UTC](https://boards.straightdope.com/t/does-this-look-real-science-or-is-it-fake/436223/19 "2008-02-05T22:09:51Z")
[QUOTE=Mangetout] I’m just amazed that something called sulphur hexafluoride isn’t horribly toxic- it sounds like it ought to be. [/QUOTE] Personally, I’m scared of sodium chloride (both sound so dangerous: sodium! and chloride!), not to mention dihydrogen monoxide. ---
**Author:** ![CalMeacham](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/calmeacham/32/35_2.png) [@CalMeacham](https://boards.straightdope.com/u/CalMeacham)\ **Post date:** [February 5, 2008, 10:13pm UTC](https://boards.straightdope.com/t/does-this-look-real-science-or-is-it-fake/436223/20 "2008-02-05T22:13:52Z")
Just to get you feeling freaky again, Sulfur Hexafluoride is structurally (and other ways) similar to Uranium Hexafluoride, one of the stable uranium compounds that was used in, for instance, isotope separation. They used to run tests with SF6 to see how well procedures with UF6 would work. [Next page](https://boards.straightdope.com/t/does-this-look-real-science-or-is-it-fake/436223.md?page=2)