/sci/ - Science & Math

no, it would only boil it, and the fire loses heat to do this as well.

>>2630934
Tell your professor is a huge moron from me

ask him why that's any different than for a house

>>2630934
this logic is also flawed, because it would mean we can inhale water into our lungs, and we would be able to absorb oxygen from it.

>>2630934

The only way to get oxygen out of water is through a process called dissociation. You can dissociate water through electrolysis (basically rusting a metal with it) or through incredibly high temperatures such as by injecting water into a 5000 degree F plasma.... please give me your professor's name and the school he teaches at, I'll make him state a retraction

this is an engineering prof right?

>>2630934
Water contains oxygen and hydrogen
Oxygen is a oxidizer, hydrogen is a propellant
Therefore water is an explosive
Makes perfect sense

>>2630934
Tell you professor he's a fucking retard. Dont use those words but...you know, paraphrase.

We use water (as well as sand and other shit) to put out fires normally. Why would it be any different in a mine?

Also... H20 isnt oxygen. Its water. The fire isnt gonna be strong enough to break the chemical bond between the O... so no, just no. Your prof is a moron

>>2630979
professor is a troll

troll wins

flawless victory

how is water 33% oxygen?
lol

If they don't use water any more it's probably because of the amount of electrical equipment in a mine these days.

http://en.wikipedia.org/wiki/Electrolysis_of_water

this is how you separate oxygen from water. whatever happens in a mine would not do it

maybe something weird happens when water is left in hot mines and you have hydrogen all over the roofs by the end of the day

>>2630980
philosophy

not really, for a normal fire its impossible
the thermolysis temperature for water is 1500° C, iirc

>>2630981
>>2630981
http://www.youtube.com/watch?v=BnHR4cMXiyM

i'm convinced this is one of many fallacies that engineering prof's tell students to challenge them and see what kind of questions they ask.

if you (and your class) just went "oh thats intradasting".jpg then you just got shit tiered

>>2630934
If we don't use water in mines it's because miners can't breathe in a gallery filled with water.
I can't see any other reason

if the fire is hot enough yes
that's why firefighter don't use water
when the H2O molecule breaks
you get 2H + O and hydrogen is explosive
but this happens at very high temperatures

i'm not sure about the right temperature but i think it was something like 1000-2000 degrees centigrade
i just remember that if the iron glows white and you use water it'll explode

>>2630963
>>2630967
>>2630975
>>2630976
>>2630979

Every four-year-old on the planet knows that water is less flammable than air.

Even a dim-witted four-year-old from a tribe, as yet untouched by civilization, in the darkest jungles of Africa would know this.

It is simply impossible that an adult, let alone one who had to pass a competency exam, would not know it.

You guys must be trolling me.

>>2630980

I knew someone was going to say hes an engineer, and their right, he is a chemical engineer to be specific. he also said that momentum is given by 0.5mv^2

>>2630999
>2H and O
kid who failed chemistry miserably and has never heard of Brinclhof detected

>>2630999 samefag
nice trips..

they do use water in mines and they use it a lot for cooling of the equipment

Your professor is right unless methane is causing the fire or explosion.

>>2630998
>>2630998
>Every four-year-old on the planet knows that water is less flammable than air.

air isn't flammable.

>>2630999

the temperature required for water to break down can be achieved in coal fires, but only if it's a big one.
only reason i see not to use water is if it's a huge fire or if your not sure what caused the fire, electrical fires obviously shouldn't be put out by water etc...

water is hardly used now days anyway, most fire extinguishers use foam, co2....

anyway the point you professor made might be valid and it might not be, really depends on the type of fire and location.

>>2631019

prove it.

>>2631031
>prove it.
When I use a lighter everything around me doesn't burn

.... i'd assume your professor was talking about a specific kind of fire? like some type of oil/grease fire? its hard to tell not having been involved in the initial conversation i cant believe any legit professor would herp so hard he derped

>>2631048
flat earth argument.

>>2631010
you don't think that H2 and O2 are instantly formed after the molecule breaks do you

>>2631048
pics or it didn't happen

>>2631051
he was talking about coal in mines that caught fire and they just leave it to burn out. I dont think he was talking about huge fires because he said they still work around it, you just see some smoke coming from the coal.

>>2631048
ingredients for fire:
1. oxygen(or something that steals electrons)
2. fuel(or something that has electron bounds and releases energy when the bound breaks)
3. temperature high enough to start the reaction

>>2630991philosophy

Ah that sounds about right.

>>2631063
i lol'd

>>2631073
again, this guy was probably just trolling your class to see if you have anybody with an actual brain in class.

http://en.wikipedia.org/wiki/Coal_seam_fire#Extinguishing_coal_fires

I'm not saying the professor is right or anything, I'm not an expert on these matters.

But I can imagine a hypothetical scenario in which, because coal mine fires happen in a very small enclosed space with shitloads of fuel, the environment heats up so much that heat is no longer a limiting factor for the fire to keep going, but rather oxygen. Water has oxygen dissolved in it, oxygen that will quickly become available to the fire when the water evaporates. So in a sense, when you pour water on a fire you are adding small amounts of oxygen to it even without having to split the H20 molecules.

In an open-air fire this oxygen would obviously be far less than the air the water is displacing so that there is a net loss of oxygen for the fire. But I can imagine the oxygen in the air reaching near-0 levels in a mine fire so that yes, the small amount of dissolved oxygen in the water is helping the fire burn.

>>2631073
charcoal burns at 1100 <span class="math">t^0[/spoiler] C
enough to cause an explosion

>>2631100

oh god, this couldn't be any fucking dumber. water doesn't just remove heat, it also excludes oxygen. god you people are dumb

>>2631111
>implying there is no oxygen dissolved in water, ever