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Posted

Here's another neat bit of information kind of like the Rhenium one that collector pointed out. Indium is also a stable element where the dominant isotope is radioactive. Naturally occuring indium is about 97% In-115 and 3% In-113. In-115 is radioactive and decays by beta decay. So in all actuallity, pure samples of indium are far more radioactive than they are stable. However, there is no need to worry since the half-life of In-115 is 440 trillion years. Thats 44 followed by 13 zeros. If you do the calculations, a gram of pure indium has an activity of around 0.36 Bq. lol. So suffice it to say, there's no need to worry since you really can't even detect activity that low. :D

Posted

I stand corrected!

This means that there are two, not one, elements with at least one stable isotope, but with a natural isotopic composition dominated by an unstable isotope.

 

However, the half life of In 115 is extreme even compared to Re 187 (4,35*10^10 yr). Consequently, the acticvity of natural In is almost none compared to natural Re.

 

A difficult question arises: how long half life can be detected? I have seen claims that Bi 209 is unstable, with a half life of ~2*10^19 years!!

 

Then what will the activity of Bi 209 be? The half life of Bi 209 is roughly 5*10^8 times the half life of Re 187, consequently the activity is (~1000Bq/g)/(5*10^8) = 2*10^-6 Bq/g. And this means about 1 radioactive decay in 6 days (in 1 gram Bi)!

 

How do you detect that??

Posted

VERY sensitive machines. Another thing with radiation is that it's not just the activity, but the energy of said activity that plays a big role. You can have a very actively decaying sample of an element, but if it gives off little to no energy in said decay, then it's not really dangerous. Look at Rhenium. The energy it gives off when Re-187 decays is 0.003 MeV. That's is absolutely nothing. (Hence why Re-187 is of no concern to people. Mix in a ridiculously long half-life with a ridiculous low decay energy, and you have what you can call a stable isotope really).

 

With In, the half-life of 440 trillion years and the decay energy of .496 MeV renders it virtually harmless. Unless my calculations were off, the activity of a one gram sample of Indium would be about 0.396 decays per second. If you're worried about that type of activity, you should just end your life now because the air around you is more "active" than that. ;):D

 

With the detection of long half-lives, I think they have very sensitive chambers composed entirely of one stable isotope of a stable element. I can only imagine the machine being incredibly expensive.

Posted

Activity.

I somewhere got the information that natural carbon (containing a small amount of C 14) have an activity of about 237 Bq/g.

 

Taking into consideration that a person of 75 kg contains about 17250 g of carbon (see webelements), this means that a human being emits a lot of radiation:

237 Bq/g * 17250g = 4 088 250 Bq

 

Well, compared to ourselves we don´t have to worry so much about a piece of Re, and even less about a piece of In. And certainly not Bi!

Posted

Yeah, I had a buddy who has a Geiger Counter do some testing on some Rhenium and Indium, and background radiation COMPLETELY drowns out any radiation emitted by the metals. So if you have them, there's nothing to worry about. The radiation is so completely weak that it can't be detected. :D

 

In other good news the word of an upcoming raise at work allowed me to spend $180 for another 5-gram button of Osmium. That should arrive next week. Now each month I should be able to afford a five gram button as long as my poker winnings continue to support me.

Posted
Oh yes' date=' of course it's the acid that dissolves. Silly me. :P HF:SbF5, if I'm correct?

 

By the way, I remembered a good page for European element collectors:

 

http://www.elemente.at.cx/

 

The page is in German, but you'll probably understand enough. :P At least I did, and I've never studied the language. The prices are reasonable, and that's the only page I've ever seen to have such a marvellous variety of elements. Some of the 1-82 range elements are missing, though, but smack me in the face if you've ever seen curium for sale before. :)[/quote']

 

Hey there Gilded. I was just looking through the earlier posts here, and that German site is really nice. They have quartz ampoules for the containment of fluorine gas. I wonder if they would ship over to the USA, or if they'd understand English if I sent them an e-mail. I'd love to get some fluorine, ampouled sodium, potassium, and lithium. (I guess their F2 is either 33% or 67% pure in Helium gas.)

Posted

Hey there everyone. I got a reply from Alex over at the site mentioned in Gilded's quote above, and yes, he speaks and understands English just fine. I am currently working on getting some more information about the fluorine gas ampoules and the alkali metal ampoules. I may actually get some real fluorine gas! :D

Posted

Hey, I've just started my element-collection but I don't know where to search on the internet. Could you give me some internet-sites ? It would be nice if there were some element-stores in Europe (I live in Belgium) !

Posted

Mendelejev, check out the link in the post I made shortly above yours. The guy there is from Austria and has a decent amount of samples for a pretty good price. I just picked up some ampouled sodium, selenium, and fluorine from him. You may also want to check out http://www.smartelements.com as Juergen has a bunch of elements for the collectors in Europe. http://www.elementsales.com is Dave Hamric's webpage, and while he is based here in the USA and is unable to ship certain items overseas, he can provide a wide range of metals for your collection.

 

It's good to see another element collector out there. It's amazing how many of us there are, yet how 'hidden' our hobby seems to be. :D Be sure to read the sticky thread here at the top of the forums and check out the periodic table over at http://www.chemicalforums.com. The pictures used in that periodic table are from my collection. :D

Posted

Thanx ! Your ellement collection is massive ! How much did you paid for it ? And how do you store your elements ? I think I'm going to make a sort of wooden book-case (??) (you must forgive me if I write some big English mistakes. I'm just a stupid Belgian sudent who tries to write in English :) ) to store all of my elements. It would be nice if the cabinet would have the shape of the periodic table with 118 little cases with the names of the elements on little metal plates. But I'm affraid it will cost to much :-(

Posted

I generally try not to think too much about how much money I've spent on my element collection :D , but from my best estimates of the money I've put into it, I'd say that it has cost me over $3000 thus far. (And I am constantly upgrading samples). Once you've put together the basic set, you start looking through your samples and thinking of which ones you want to upgrade. I'm constantly doing that, and as a result, obtaining bigger and better samples. Another thing I had on my side was timing. It seems as if whenever I was looking for a certain element, I was able to find it at a great price. (Like my Rhodium which I got for a bit over $200 but is now worth more than twice that, and the lab-made diamonds I purchased, the white phosphorus, the rubidium, the cesium, etc. I was able to find a seller of those items at a time in which I had money and was looking for them). I think the biggest thing to remember is that this is a collection and a hobby at the same time. So don't feel as though you have to rush out there to pick up everything at once. Start small and try to collect certain groups at first. What many people do is start out with the Lanthanoids. They are relatively cheap and fairly easy to get nice samples of at a good price. Once that is complete, move on to the oxygen group, or the halogens, or the noble gases, or the group 1 then group 2 metals. Etc. etc. If you set those small goals for yourself, it's MUCH easier to put together a full collection with great looking samples.

 

Another thing to remember is that when looking to buy a sample, find a good price/amount ratio. If it costs you $300 to get a 20 gram sample of an element, but it will only cost you $350 to get a 28 gram sample, hold off on the purchase until you can pony up that extra 50 dollars. You'll thank yourself later for that. For the PGMs, many times it's easier to purchase smaller amounts on numerous occasions, rather than once big amount all at once. I now have over an ounce of gold, but I got that ounce by buying small 1-5 gram samples over the course of a few years. After a while, it all added up to over an ounce. While I probably spent far more on those little pieces than I did if I just saved up to buy a whole ounce, I didn't have to pony it up all at once. I guess you could say it was kind of like a credit card, and the extra amount I paid for the smaller pieces was like the interest on the credit card. I would have loved to have bought the ounce all at once, but psychologically it's a bit easier to spend $40 ten times than it is $400 all at once.

 

For storage, I have a wooden cabinet in my bedroom which is what my computer is on. (It's a fancy computer desk with fairly large cabinets underneath it). Inside the cabinet are a couple of fireproof safes. They're small, but they do the job. The halogens are stored in one very small safe away from everything else, and the Alkali and Alkaline-Earth metals are stored in a separate safe. Everything else is stored in the containers they've been photographed in inside the empty space in the cabinets. The white phosphorus is kept inside the container it was shipped in which is basically a metal can with a foam center that has a little area cut out to accept the 20 mL vial. It does not see any daylight. My Depleted Uranium samples are stored inside a 20mL vial which is in a lead sarcophogus of sorts inside a custom made (by me) wooden box which is lined with lead sheeting. Absolutely no radiation is detectable outside the box. The noble gases and gas discharge tubes are wrapped in bubble wrap and stored in a closet. The cabinet holding the elements also has a lock and key to it for security reasons. (There's a lot of expensive precious metals inside there that I'm not about to let some low-life steal).

 

I too would like to have a nice display cabient with sections for each of my elements, but that's something that I'll have to hold off on doing until I have my own house. (I already have my ultimate room setup in my mind. A nice wetbar, an arcade cabinet in the corner, a pool table, a bigscreen TV, and on one of the walls my element collection in a cabinet set up like a periodic table. :D)

Posted

I would like to make my own sample of iron. Could I make it with the thermite reaction ? And would it be pure enough ?? And could I use Al203 or CuO instead of Fe2O3 ?

Posted
I would like to make my own sample of iron. Could I make it with the thermite reaction ? And would it be pure enough ?? And could I use Al203 or CuO instead of Fe2O3 ?

 

Yes that will work. You will need to use Fe2O3 though. Whether it will be pure enough is entirely subjective and depends on how pure you want it. Attached is my iron sample made with thermite. Obviously its not extremely pure as you can see the impurities but I am happy with it.

iron.jpeg

Posted

The method behind the thermite reaction is that the aluminum atoms vigorously rip the oxygen atoms off of the iron in order to form aluminum oxide and release a LOT of energy. In fact, so much energy is given off that the iron forms as a liquid. If you use copper oxide instead of iron oxide, you'll just produce copper. Whatever oxide you use is what pure metal you'll wind up with.

Posted
you shouldnt get a good yield of iron at all. yes, you get the molten metal, but it oxidizes easily at such high temperatures

 

Yes, but its at least 13 times more interesting than a nail.

Posted

So you just take the external layers and polish them off. The iron that is not exposed to the surrounding air cannot be oxidized. :D

Posted

"drip it into a bottle of like neon"

argon and helium are significantly cheaper.

 

"Yes, but its at least 13 times more interesting than a nail."

agreed.

 

"So you just take the external layers and polish them off. The iron that is not exposed to the surrounding air cannot be oxidized."

true, that, although it diminishes product quantity

Posted

But with a thermite, you generally produce a heck of a lot of it. ;) (At least in the good thermites. :D )

  • 2 weeks later...
Posted

Hi

 

A guy I bought group II elements is selling In, Zn, Mn, Ge, Cr, Bi, Sb, Ca, Mg, Ta, Na, I, B, Yb tommrow. I'm not sure how he's planning to sell them ie. in groups etc. His ebay name is kkjc2.

 

Just thought it was worth mentioning :) .

Posted

We'll have to keep him in mind in terms of sources for elements. This past week has been great for me in terms of my collection. I received a few things in the mail and got a few more things for a really good price. I picked up a 1/10th ounce gold maple leaf for melt price, a 5-gram gold bar for melt price, 10+ carats of rough uncut diamonds, a 1/10th ounce platinum maple leaf, some fluorine gas, some unoxidized sodium metal in a sealed ampoule, some amorphous selenium, a larger chunk of europium, some more nickel thanks to some Canadian quarters and dimes received in change, some black phosphorus, and some more osmium. I didn't pay anything exorbinant for either of the items. (I'm excited about the diamonds because 10+ carats is over two grams of raw diamonds. These things aren't of a high enough quality to be cut and used as jewelry, so they are PERFECT for the element collection as some allotropic carbon). It's always nice going through these little periods where you can find a bunch of elements that you want/need and you don't have to pay through your teeth for them. (Now combined I spent a good deal of money on all of those items, but at any one purchase I didn't spend a ton so it was was easier to afford).

Posted

Yesterday when I went to see the hitchhikers guide I dropped by this hippie type store (the local movie theater is in a mall). I was looking around and they had this table with all sorts of rocks and minerals. I noticed a basket of silicon looking chunks with the label "silicon" with a price tag of $2 each. Of course I'm not just going to walk by it so I pick one up and ask the guy if he knows how pure it is. He said all he knew was that they were too pure for computer chips.

 

I think hes full of shit but I bought a chunk and it looks and feels like silicon so thats good enough for me. Anyway, its a rather nice sample and it weighs 40g.

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