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[Vector]

Does this sound like it would work? How could I heat the metal without melting everything?

...

You find a metal with a high enough melting point, i.e. something that melts above 1500 degrees F or so.  I'd also be careful to make allowances for water evaporation over time; don't know how advanced your course is, but I definitely remember doing something like that in my college intro.

[Siquo]

Does this sound like it would work? How could I heat the metal without melting everything?

That could work but is hopelessly inaccurate (as was my idea). The metal cools really quickly in air so you need to drop it in the water instantly, the water-container should be very well insulated, and heat will leak out of the container while the metal cools and the water heats up. The water will instantly boil around the metal, and there's a chance that it will boil so quickly that it'll explode and you'll be covered with boiling water. Not good.

Also you'll need tongs of some kind that could hold the metal while it is hot, and that don't melt. Iron probably won't do. Ceramics are pretty heat resistant and non-heat-conductive though, perhaps you could make something to hold it with a ceramic stand.

[BKWM]

uhmm, bunsen burners don't melt iron. They come really close, but they don't melt it. tried for like three hours with an iron nail.

[Siquo]

Well then, there's your answer! Use Iron! And Magma!

How about using the expansion coefficient of iron and measure the length of an iron nail to determine the temperature?

[BKWM]

because the flame isn't uniformly hot.

also it's somewhere in the range 1450 C

[Siquo]

No, but the nail, if not much larger than the flame, can be considered uniformly hot because of the heat conductivity. The error margin that introduces should be in the same league as trying to measure the length of a 1400 degree iron nail with a ruler. Tip: don't use a plastic ruler

[Virex]

No, but the nail, if not much larger than the flame, can be considered uniformly hot because of the heat conductivity. The error margin that introduces should be in the same league as trying to measure the length of a 1400 degree iron nail with a ruler. Tip: don't use a plastic ruler

The  expansion of a nail, even at those temperatures, is going to be in the order of percents. With a small nail and a ruler that'll give you a huge error margin. You'd probably be better off by making yourself a bi-metal strip termomether, though you making a scale for it would require some tricks (unless you know some substances with a boiling point of 1000 celcius?)

[ChairmanPoo]

I dont understand why finding out the flame spectre (which should be easy enough) is off-limits and complicated methods which involve millimetric measurements of very hot nails (and which at least at a glance seem rather error-prone) are not 

[AtomicPaperclip]

Well I don't know anything about expansional properties of iron or finding temperatures through spectrum.

I asked him if I could use iron and he said I was on the right track.

We did a similar lab to find the specific heat of a metal, but 1500 degrees makes so many more complications.

He did mention that in that lab the transfer time was bad, and asked us to think about how to improve it.

We're 12 weeks through and it's not an honors class, we haven't covered a whole lot =/

[Virex]

If you can find the specific heat of Iron, then you could do it with a simple adiabatic calorimeter with a water bath (ask one, it's probably standard issue lab equipment, or else you can botch one up with a beaker and isolation foam). Heat the iron for a long time, so it'll reach the same temperature as the flame, then drop it into the calorimeter and measure the maximum temperature. If you know the amount of water in the calorimeter and the specific heat of iron and water (and the calorimeter itself if you'd want to be very precise), calculating the initial temperature of the iron is quite simple.

[AtomicPaperclip]

well the specific heat of iron is on my periodic table of elements, and I've never used a calorimeter but I could calculate it, that's the idea.

[Siquo]

I dont understand why finding out the flame spectre (which should be easy enough) is off-limits and complicated methods which involve millimetric measurements of very hot nails (and which at least at a glance seem rather error-prone) are not 

Because
A: the flame spectrum is dependent on the burned chemicals, largely temperature independent and
B: the blackbody radiation by a flame of this type is hard to detect, because of the blue ionised air. The color blue in blackbody radiation spectra is about 10000K.

Although you could measure it using an Infrared temperature reader, if you have one lying around with a scale that's high enough...

[Funk]

what gas/gas's are you bruning.
what is gas's pressures.

it may well be that its just useing Propane or Butane.

[ChairmanPoo]

so I was wrong after all. Damn.

Should have figured out that the flame color is not binding. It's not like it isn't common knowledge (special effects, fireworks, etc...)

[MagmaDeath]

That's Easy, I had to do this a few days ago.
Heat an Iron nut, Stick it into a calorimeter filled with water.
(You could use two Styrofoam cups)
Measure the temperature before and after you insert the nut, take the mass of the water before and after, Use a few thermochem Equations and that's it.

And I was ninjad