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Post by Beatsy »

I recently found a small (31 x 3.5 x 0.05mm) strip of platinum in a random bits box. Roughly a tenth of a gram or so. It's the straightened-out heating element from a needle puller. Not worth chopping in for bullion, my left sock is probably worth more, so I kept it. But now it just sits there being irritatingly boring, nonreactive platinum and I can't think of anything interesting to do with it, or use it for.

Surely, there must be *something*!

Any ideas...?

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Post by mawyatt »

Research is like a treasure hunt, you don't know where to look or what you'll find!

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Post by Sym P. le »

Heavy! 8)

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Post by JW »

Form it into a loop with handle, and use the looped end as a holder to burn stuff in a flame

Stick it in hydrogen peroxide (must be clean) and make some H2 and O2 bubbles - may be a slow reaction, though
It's not what you look at that matters, it's what you see - Henry David Thoreau

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Post by Smokedaddy »

... isn't platinum radioactive?

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Post by ChrisR »

Smokedaddy wrote:... isn't platinum radioactive?
I think that would be plutonium, Jim ;)
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Post by Smokedaddy »

Six naturally occurring isotopes of platinum exist: platinum-190, platinum-192, platinum-194, platinum-195, platinum-196, and platinum-198. Of these, only platinum-190 is radioactive. ... These isotopes are produced when very small particles are fired at atoms. These particles stick in the atoms and make them radioactive.
Last edited by Smokedaddy on Thu Mar 05, 2020 9:20 am, edited 1 time in total.

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Post by Smokedaddy »

I was thinking you could make a Cloud Chamber.


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Post by rjlittlefield »

Smokedaddy wrote: platinum-190 is radioactive
was thinking you could make a Cloud Chamber
Right, but check the half-life and abundance. says 6.5E+11 years and 0.012% .

I'm also seeing atomic weight of 195 gm/mole and density of 21.45 gm/cm^3 .

From there, my spreadsheet works the sums as...

mass of Beatsy's sample = (31mm x 3.5 mm x 0.05 mm) * (0.001 cm^3/mm^3) * (21.45 gm/cm^3) = 0.116 gm
moles of Beaty's sample = 0.116 gm / 195 gm/mole = 0.000597 moles of mixed platinum
moles of Pt-190 = 0.000597 * 0.012% = 7.16E-08
atoms of Pt-190 = 7.16E-08 *6.02E+23 (Avogadro's number) = 4.31E+16
disintegrations/year = 4.31E+16 * 0.5 / 6.5E+11 = 3.32E+4
disintegrations/second = 3.32E+4 / 3.15E+07 = 1.05E-03
seconds/disintegration = 1/1.05E-03 = 950

So, roughly 1 disintegration every 16 minutes, for Beatsy's sample?

That's more than I expected, but might be a little boring anyway. :(


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Post by Bob-O-Rama »

I have some 1oz platinum crucibles my dad used in grad school. He kept the original receipt from the Syracuse U bookstore c. 1962 in his papers: they were $12 each.

There are a lot of catalytic reactions you can demonstrate with a small piece like you have.

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