This sounds like it would merit inclusion in Derek Lowe's "Things I won't work with":
“Only a few facilities around the world can protect both the compound and the worker while managing the combined hazards of a highly radioactive material that reacts vigorously with the oxygen and moisture in air,” said Polly Arnold, a co-corresponding author on the paper.
It's like they decided flourine wasn't dangerous enough, so they made it radioactive too!
How fast does it evaporate in a vacuum?
It's a very hard question, borderline impossible with the current technology [1], but if you allow me to handwave and lie and lie even more:
It's a very heavy molecule.
The top "bread" of the sandwich has 14 Carbons and a few undraw Hydrogen, I guess 16. So the weight is 12×14+16×1 =184
Double that for the other "bread".
The "meatball" in the center is Berkelium 247.
So the total weight is 184+184+247=615.
Assuming the Berkelium is totaly covered, the exterior part is similar to Hydrocarbons in oil. There are many, so let's try to pick the correct one.
Each Carbon usually has two Hydrogen, so the weight is 14×num_C, so the number of Carbons in a fake equivalent is 615/14~=44.
Hydrocarbons in gasoline have like 6-10 Carbons, diesel has like 12-20. Parafin wax https://en.m.wikipedia.org/wiki/Paraffin_wax has 20-40 Carbons per molecule.
So this molecule is closer to heavy parafin wax.
Double bonds are also important, and this molecule has a lot of them, but my handwaving is not strong enough to deal with it.
> How fast does it evaporate in a vacuum?
I guess it will take forever.
[1] Edit: without a sample, you can probably measure it in the lab with a big enough sample.
Probably not that long, uranocene (a comparatively heavy molecule of similar structure) apparently has an appreciable vapor pressure of 10^-3 torr or so at 200C.
Weight does matter of course, but intermolecular bonding/affinity is generally the more important consideration.
Yes, I agree, but ...
> Probably not that long, uranocene (a comparatively heavy molecule of similar structure) apparently has an appreciable vapor pressure of 10^-3 torr or so at 200C.
200°C(392°F) is hotter than boiling cooking oil (it's a hot oven to cook, but far from red hot)
vapor pressure of water at 0°C(32°F) is 5 torr
i.e. almost frozen water has 5000x the vapor pressure of very hot uranocele.
Let's replace "forever" with "extremely slowly".
> Weight does matter of course, but intermolecular bonding/affinity is generally the more important consideration.
I agree, so I choose a non-polar material to compare. (i.e. petrol instead of water). Probably petrol and parafin are very saturated and linear, and both change the properties of the molecules a lot. I'd better have choose something with more double bounds, but I don't have a very good example at hand.
249Bk half-life is 330 days.
A solid kilogram of it would be a lot of decays in a small area. It would heat up close to its melting point before glowing brightly enough in infrared to shed the heat as quickly as it's generated.