# Chemical formula for 'dry' water ~ sapphire? **URL:** \ **Category:** Factual Questions\ **Created:** [August 19, 2004, 2:31pm UTC](https://boards.straightdope.com/t/chemical-formula-for-dry-water-sapphire/260549 "2004-08-19T14:31:29Z")\ **Posts on this page:** 9\ **Page:** 2
**Author:** ![Shalmanese](https://avatars.discourse-cdn.com/v4/letter/s/45deac/32.png) [@Shalmanese](https://boards.straightdope.com/u/Shalmanese)\ **Post date:** [August 20, 2004, 4:45am UTC](https://boards.straightdope.com/t/chemical-formula-for-dry-water-sapphire/260549/21 "2004-08-20T04:45:40Z")
> [@astro](#): > > Umm… has this notebook into “Sapphire” test been done before? Because if this stuff has any kind of insulating properties it better be an old laptop with a slow CPU, or a cool running notebook, or that CPU is going to fry once the liquid insulates it unless the dip is only for a few seconds. you mean, more insulating than air? :dubious: ---
**Author:** ![astro](https://avatars.discourse-cdn.com/v4/letter/a/9dc877/32.png) [@astro](https://boards.straightdope.com/u/astro)\ **Post date:** [August 20, 2004, 5:32am UTC](https://boards.straightdope.com/t/chemical-formula-for-dry-water-sapphire/260549/22 "2004-08-20T05:32:40Z")
> [@Shalmanese](#): > > you mean, more insulating than air? :dubious: Air _with a fan(s)_ usually moving that air in most modern notebooks. Considering the properties of the mateial being described it does not sound likely that a fan will be able to operate efficiently in that environment. I do not know the thermal insualting properties of this “sapphire” material. If it’s more heat conductive than air there may well be no issues, but sticking an operating notebook into a fluidic type substance that is almost guaranteed to stop the system ventilation fan due to its relative viscosity does not sound like a particualrly good idea (to me). ---
**Author:** ![Colophon](https://avatars.discourse-cdn.com/v4/letter/c/f05b48/32.png) [@Colophon](https://boards.straightdope.com/u/Colophon)\ **Post date:** [August 20, 2004, 10:50am UTC](https://boards.straightdope.com/t/chemical-formula-for-dry-water-sapphire/260549/23 "2004-08-20T10:50:26Z")
> [@astro](#): > > Umm… has this notebook into “Sapphire” test been done before? Yes it has - and [here are the pics](http://www.technovelgy.com/ct/Science-Fiction-News.asp?NewsNum=94) to prove it. 🆒 ---
**Author:** ![Shalmanese](https://avatars.discourse-cdn.com/v4/letter/s/45deac/32.png) [@Shalmanese](https://boards.straightdope.com/u/Shalmanese)\ **Post date:** [August 20, 2004, 12:26pm UTC](https://boards.straightdope.com/t/chemical-formula-for-dry-water-sapphire/260549/24 "2004-08-20T12:26:29Z")
> [@astro](#): > > Air _with a fan(s)_ usually moving that air in most modern notebooks. Considering the properties of the mateial being described it does not sound likely that a fan will be able to operate efficiently in that environment. > > I do not know the thermal insualting properties of this “sapphire” material. If it’s more heat conductive than air there may well be no issues, but sticking an operating notebook into a fluidic type substance that is almost guaranteed to stop the system ventilation fan due to its relative viscosity does not sound like a particualrly good idea (to me). It’s a moot point, Sapphire boils at 49C which is significantly lower than the maximum safe operating temp of laptop CPUs. ---
**Author:** ![Johnny\_L.A](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/johnny_l.a/32/1084_2.png) [@Johnny\_L.A](https://boards.straightdope.com/u/Johnny_L.A)\ **Post date:** [August 20, 2004, 1:06pm UTC](https://boards.straightdope.com/t/chemical-formula-for-dry-water-sapphire/260549/25 "2004-08-20T13:06:07Z")
Why bother with the formula for “dry” water? [url=“[http://pw1.netcom.com/~heliboy/dehydrated\_water.jpg](http://pw1.netcom.com/~heliboy/dehydrated_water.jpg)”]Just buy it by the tin\*! 😃 ---
**Author:** ![Johnny\_L.A](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/johnny_l.a/32/1084_2.png) [@Johnny\_L.A](https://boards.straightdope.com/u/Johnny_L.A)\ **Post date:** [August 20, 2004, 1:07pm UTC](https://boards.straightdope.com/t/chemical-formula-for-dry-water-sapphire/260549/26 "2004-08-20T13:07:21Z")
Why bother with the formula for “dry” water? [Just buy it by the tin](http://pw1.netcom.com/~heliboy/dehydrated_water.jpg)! 😃 ---
**Author:** ![bizzwire](https://avatars.discourse-cdn.com/v4/letter/b/958977/32.png) [@bizzwire](https://boards.straightdope.com/u/bizzwire)\ **Post date:** [August 21, 2004, 2:17am UTC](https://boards.straightdope.com/t/chemical-formula-for-dry-water-sapphire/260549/27 "2004-08-21T02:17:08Z")
> [@Colophon](#): > > How do you figure that? Even once it’s evaporated, it’ll still act as an asphyxiant and keep oxygen away from the fire. Halon is already a gas, so requires precisely sod-all energy to evaporate, and that puts out fires pretty well. You don’t need a liquid to put out a fire; simply something that takes away at least one part of the fire triangle (Fuel - Heat - Oxygen). Well, as the 3M guy said: > [@](#): > > The fluid, produced by 3M, has weak molecular bonds and vapourises at just 49° Celsius, 51 degrees cooler than the temperature at which water boils.\*\* It stops fires before they get out of control by soaking up heat from the nascent blaze. \*\* Bolding mine. So, one of the ways water fights fires is by sucking up heat energy (and evaporating into water vapor in the process). It will only act as an “asphyxiant” if the fire is in a closed environment (but then, so does the carbon dioxide produced). Something with a lower boiling point will suck up less heat, so I don’t understand why 3M is bragging about the low boiling point. The other thing about Halon (and other halogenated compounds) is that it interupts the chemistry of combustion by acting as a free-radical “sink.” Halogens are excellent free-radical scavengers, shutting down the chain-reaction process of combustion. Remember the old-style fire extinguishers which were nothing more than a container of cabon tetrachloride? ---
**Author:** ![LH75](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lh75/32/4438_2.png) [@LH75](https://boards.straightdope.com/u/LH75)\ **Post date:** [August 21, 2004, 4:53am UTC](https://boards.straightdope.com/t/chemical-formula-for-dry-water-sapphire/260549/28 "2004-08-21T04:53:31Z")
friend bizwire, > [@](#): > > Remember the old-style fire extinguishers which were nothing more than a container of cabon tetrachloride? carbon tet does an amazing job of putting out fires. our small museum has a few glass balls filled with carbon tet that sit in brackets. the idea was to take the glass ball and throw it at the base of the fire. small problem: when carbon tet is heated it gives of phosgene gas, a cumulative poison… ---
**Author:** ![antechinus](https://avatars.discourse-cdn.com/v4/letter/a/fbc32d/32.png) [@antechinus](https://boards.straightdope.com/u/antechinus)\ **Post date:** [August 21, 2004, 5:11am UTC](https://boards.straightdope.com/t/chemical-formula-for-dry-water-sapphire/260549/29 "2004-08-21T05:11:52Z")
> [@bizzwire](#): > > The other thing about Halon (and other halogenated compounds) is that it interupts the chemistry of combustion by acting as a free-radical “sink.” Halogens are excellent free-radical scavengers, shutting down the chain-reaction process of combustion. Remember the old-style fire extinguishers which were nothing more than a container of cabon tetrachloride? To expand on this; the first step in combustion is the formation of a free radical when, say, a C-H bond in a hydrocarbon is cleaved by heat to give a hydrocarbon free radical and a hydrogen free radical e.g. ```auto H H | | R--C--H --> R--C. .H | | H H ``` The free radicals then react with oxygen to release more heat. This starts the chain reaction. A free radical inhibitor, such as the fire retardant, terminates the chain reactions by reacting its own free radicals with the combustion free radicals without producing more heat. [Previous page](https://boards.straightdope.com/t/chemical-formula-for-dry-water-sapphire/260549.md?page=1)