Are metals burnable?

:cool: Tool steel would probably survive a structure fire, but it would need to be rehardened and tempered...Steel will burn. I learned this the hard way by not paying attention when I first started forging blades...Almost had a blade that looked like I knew what I was doing...got distracted (running my mouth) then I saw sparks flying from the forge...grabbed the tongs to get my blade out and it was almost burnt in half!! :grumpy: You can change the grain structure of steel...after a blade is forged and ground to shape, use thermal cycles, get steel to critical temp. which is the point at which steel becomes non-magnetic, then letting it cool to room temp. in still air...three cycles using less heat each cycle...this causes the grain structure of the steel to become finer, which is what you want in a blade....If the blade gets too hot the grain grows bigger....contact me if you have any more questions about this, I can tell you better than I can write about it....remember....Hit it while it's HOT!!!
 
Metallic sodium is neat. High school chemistry teachers may have some on hand for demonstrations. Mine did, and it was in a large thing filled with oil, she cut a small piece off of what I recall being a softball sized lump of it and dropped it in a beaker of water. I've heard of stupid human stories where a guy would steal some from the science lab and put it in his pocket, obviously with disasterous results :eek:
 
Rich S said:
Actually it's H2 (hydrogen is diatomic :-)

Most metals will burn if gotten hot enough.
Mixture of aluminum and iron oxide is called thermite; used for
bombs and use to be used to weld railroad track. Magnesium
for underwater flares.
Group IA metals and some of the Group IIA are highly reactive to
water producing H2 in a very exothermic reaction which will
commonly ignite the H2.

Rich S (ye olde chemistry prof)
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Typical professor to say something is wrong, and then not show the correct answer: :rolleyes:

2Na + 2H2O --> 2NaOH + H2
 
We were on one of the lakes in Minn and waiting for one friend who came late, after dark. We heard a motorboat and thougt it might be him. The chemist took a LARGE chunk of sodium out of a bottle and threw it into the lake. Did you ever see photos of an ammunition ship explode ? It was just like that with lots of streamers shooting high into the sky !! Our friend knew it was us ...As has been mentioned magnesiun burns violently. I remember a truck loaded with Magnesium crashing and burning on the Chicago expressway . They had to replace a section of the expressway the steel structure melted ! Chemistry in action !!
 
sheltot said:
Typical professor to say something is wrong, and then not show the correct answer: :rolleyes:

2Na + 2H2O --> 2NaOH + H2
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If us old geezer professor types told you all the answers then you youngens
would never learn to think for yourselves :-)

Rich S
 
Gollnick said:
Anything and everything will burn if you get it hot enough.
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Not if it's already been completely oxidized, unless you add a more powerful oxidant to the mix. Under ordinary conditions (oxygen/nitrogen atmosphere), things like rust, water, and carbon dioxide won't burn at any temperature because they've already been 'burned'.

Bill D.
 
With Tsme's last comment we have sort of come full circle. As he mentions: "Under ordinary conditions (oxygen/nitrogen atmosphere), things like rust, water, and carbon dioxide won't burn at any temperature because they've already been 'burned'." In these cases what has previously been burned is: iron (to form rust, Fe2O3)), hydrogen (to form water, H2O), and carbon (to form CO2). Yet if you have a very reactive metal like magnesium you can "unburn" these materials. If you heat magnesium and get it burning it will pull the oxygen back out of: rust (leaving molten iron-the thermite reaction), water (to leave hydrogen), and carbon dioxide (to leave carbon). This is why metal fires are so difficult to put out.
 
Jeff Clark said:
With Tsme's last comment we have sort of come full circle. As he mentions: "Under ordinary conditions (oxygen/nitrogen atmosphere), things like rust, water, and carbon dioxide won't burn at any temperature because they've already been 'burned'." In these cases what has previously been burned is: iron (to form rust, Fe2O3)), hydrogen (to form water, H2O), and carbon (to form CO2). Yet if you have a very reactive metal like magnesium you can "unburn" these materials. If you heat magnesium and get it burning it will pull the oxygen back out of: rust (leaving molten iron-the thermite reaction), water (to leave hydrogen), and carbon dioxide (to leave carbon). This is why metal fires are so difficult to put out.
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Excellent point about "unburning". I should have been more careful and noted that I listed some products of combustion, not the actual substances that had burned to produce these products. Thanks for the correction.

We had a terrible traffic accident in a freeway tunnel in my area some years ago, involving a gasoline tanker. After the gas was all burned up, some of the metals (aluminum, etc,) continued to burn for hours. :eek:

Bill D.
 
Tsme, I didn't mean my comment as a correction, merely an elaboration of your comment. I've had a lot of fun demonstrating replacement reactions to school kids so they're kind of familiar. The thermite reaction is the best. Take a little rust and a little powdered aluminum and melt through a steel plate. It's also interesting to see what metals you can dissolve away with copper sulphate.
 
So, everything can be burn if they are hot enough? Besides water obviously... Am i right?

Also, if a metal is burnout, will it becomes water and carbon dioxide like a candle does?:confused:
 
ckl said:
Also, if a metal is burnout, will it becomes water and carbon dioxide like a candle does?:confused:
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Obviously not: water and carbon dioxide is H2O and CO2, which means carbon, hydrogen and oxygen. Carbon and hydrogen come from your fuel: here candle which is generally parafin, which is an hydrocarbon product somewhat like oil (hydrocarbon: hydrogen+carbon, here they are).

Oxygen comes from atmosphere.

What we call burning is oxydation. So burning metal would get you metal oxide.

By the way word "oxygen" is obviously linked to that process: "oxy-gen" (generates oxydation). Due to its electronegativity, oxygen forms chemical bonds with almost all other elements (which is the origin of the original definition of oxidation), which makes it very "aggressive" (as a matter of example see also "hydrogen peroxide", which burn skin on high concentration and is often use to clean hunting trophies from head to skull).

Oxygen might also be replaced by some other gases with close properties, but it is the most refered because extremely common and very active.
 
iron (to form rust, Fe2O3
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Just to join the nitpicking society, rust usually is iron hydroxide, depending on the conditions it apparently can be a mixture of oxide and hydroxide.

Not that it changes things much.

TLM
 
I've never seen a metal lit on fire (except for some magnesium) but I know I have left some nasty burn marks on steel with an angle grinder.

And for getting pure sodium: I found out from my chemistry teacher yesterday that you need a site liscence (Around here anyways.)

On a relatated note... Does anyone know where I would go to find some pure aluminum powder?
 
Iron hydroxide is just an intermediate stage in the rusting process. The final stage is Fe2O3. (hydrated--with water molecules linked on the outside).

= = = = = = = = = Here's a textbook explanation = = = = = = = =

When steel contacts water, an electrochemical process starts. On the surface of the metal, iron is oxidised to iron(II):

Fe → Fe2+ + 2e-
The electrons released travel to the edges of the water droplet, where there is plenty of dissolved oxygen. They reduce the oxygen and water to hydroxide ions:

4e- + O2 + 2H2O → 4OH-
The hydroxide ions react with the iron(II) ions and more dissolved oxygen to form iron oxide. The hydration is variable, however in its most general form:

Fe2+ + 2OH- → Fe(OH)2
4Fe(OH)2 + O2 → 2(Fe2O3.xH2O) + 2H2O
 
Ravaillac said:
What we call burning is oxydation. So burning metal would get you metal oxide.

Thanks guys... So, one metal oxide was created, is it possible to restore it to metal?

And is there a diffirence btn burning and melting of a metal? Does melting only turns the metal in a liquid form but not to oxidize it?

Oh yeah i got interested in chemistry.;)
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Melting is just iron to iron, no oxide formed.

Burning forms an oxide. :)

Could you deoxidize metal? Sure. A strong reducing agent would do it, but metal deposition would be random.
 
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