Elementary Productions: The Leidenfrost effect

A Red Hot glowing copper coin is added to Methanol. As the copper coin is much hotter than the boiling point of Methanol, it is surrounded by a "protective" layer of Methanol vapor, keeping the Methanol from touching the copper coin. As the copper coin cools, this layer collapses, exposing itself to the Methanol and brings about a second boil.

Category:

Science & Technology

Tags:

• leidenfrost
• effect
• methanol
• boil
• phase
• transition
• copper
• coin

[zasx20]

the same thing is happining with dry ice when it can be use to play "air hocky" corect?

[mabakken]

That is absolutely correct. =)

[mabakken]

I'm sorry, could you please elbaorate on the question?

[pyropakman]

I did this to a copper penny today, and upon adding it, this exact thing happened.

Only difference is, there was a pungent smell of formaldehyde as well. Possible copper oxide oxidizing the methanol? How though?

[dragonridley]

I think I saw something similar to this when someone poured liquid methane on Jay Leno's stage.

[edga69]

Hi, I put Cu, Al and Steel into liquid nitrogen. For all of these there was a small dip in the graph, then a big one (at the leidenfrost point). Why is there the first small dip? Thanks for any help :)

[Ulti13]

Can you make this with Ethanol or Aceton too?

[mabakken]

If you heat a coin in air, it usually turns black due to the formation of the oxide. As you submerge it in Methanol, the hot oxide reacts with the Methanol, and turns it into a brown Oxide.

This is the basic idea behind your results.

Hope it can be of help =)