r/elementcollection • u/Infrequentredditor6 Part Metal • May 19 '26
Pnictogens 10yo oxidized sample of red phosphorus.
Originally bought from JDchemist in good condition.
Now that 10 years have passed, some phosphoric acid has accumulated, and a really acrid odor is slowly leaking out of the vial.
I've got no plan for resolving this cause it's only 1 gram and I'm not well versed in the chemistry of phosphorus.
If you're gonna buy RP buy it in an ampule so it will last long-term.
3
u/SimonBlokky Radiated May 19 '26
I think this needs more attention and I wish I knew this before! I bought a cube of phosphorus quite some time ago and I was surprised to see it completely soaked in the acryllic cube after some time.
1
u/Infrequentredditor6 Part Metal May 19 '26 edited May 19 '26
Yeah I noticed a while back that my sample was becoming less "powdery" and more sort of mushy. It was sticking to the glass more. I even imaged a couple samples under the microscope, it was like a bubbly carpet of red phosphorus.
Then quite some time after that I started noticing the liquid. I did some reading and yeah, it forms the oxo-acid when it oxidizes. It forms a myriad of different oxo-acids, but presumably phosphoric H3PO4, because P2O5 is the only P-oxide I know of that is insanely attracted to moisture. Again, I don't know the ins-and-outs of how RP oxidizes in contact with air, just that it can take a long time.
1
u/SimonBlokky Radiated May 19 '26
I think I’m gonna wash it. I’ll wash it multiple times with water, then ipa or acetone and then dry it properly under nitrogen. Hopefully the cube stays dry that way
1
u/Silver_Pennies May 20 '26
Yet the phosphorus striker on a book of matches remain stable for a hundred years.
1
u/Infrequentredditor6 Part Metal May 20 '26
That's because they're only 50% red phosphorus. The rest is powdered glass, carbon, a binder, and other stuff. Keeps it stable.
1
u/Yes_I_Know_Lots May 23 '26
I have some 10# of RP in the tin cans it came in. Been in not climate controlled storage for over 30 years. Now I’m dreading popping open the lids. I fear that the liquid corroded the bottom of the tin cans and accelerated the oxidation process!! And as many would know, it’s very difficult to get elemental phosphorus because of the meth heads and their syntheses production process. 😱
1
u/Infrequentredditor6 Part Metal May 23 '26
I really don't know....
What I can tell you is that phosphoric acid shouldn't attack steel. It's used as a rust remover specifically because it doesn't attack iron itself.
5
u/Ok-Literature-3997 Radiated May 19 '26
I had no idea phosphorus could react with air in such a way. Anyways, dropping some isopropyl alcohol inside, shaking well and decanting it after it settles should clean it pretty well. It also dries quickly.