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Topic: Largest Molecule that is still a gas  (Read 7314 times)

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Offline curiouscat

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Largest Molecule that is still a gas
« on: August 20, 2012, 11:05:42 AM »
Generally (very crudely) as molecular size increases it is less likely that a molecule is gaseous (say at Room Temp).

Got me thinking: what's the highest MW molecule that is still gaseous? Let's say, BP <20 C at 1 atm.

I can think of Radon (MW 222 ; BP -60 C) or SF6 (MW 146 ;  BP -64 C )

Alternatively, what's the molecule with the largest (number of constituent atoms) that is still a gas?

Wondering how high we can go? Especially interesting among hydrocarbons.

Offline fledarmus

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Re: Largest Molecule that is still a gas
« Reply #1 on: August 20, 2012, 03:34:16 PM »
Going down the periodic table, SeF6 and TeF6 are both still gases, the later at MW ~ 242 and bp ~-40°C. Wikipedia shows that PoF6 (MW 323) has been synthesized and was predicted to have a bp around -40°C, but I haven't seen the measurement.

Offline Borek

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Re: Largest Molecule that is still a gas
« Reply #2 on: August 20, 2012, 04:02:51 PM »
WF6?
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Offline curiouscat

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Re: Largest Molecule that is still a gas
« Reply #3 on: August 21, 2012, 02:27:20 PM »
WF6?

That does seem the highest so far. Thanks!

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