Naked Science Forum

Non Life Sciences => Chemistry => Topic started by: spook1456 on 16/04/2011 15:26:49

Title: I heard that uranium238 has the longest half-life, are there any longer ones?
Post by: spook1456 on 16/04/2011 15:26:49

I heard that uranium 238 has the longest half life of 4.51 billion years , are there any elements with longer half lives than uranium 238 ( and what element has the shortest half-life?)

Title: I heard that uranium238 has the longest half-life, are there any longer ones?
Post by: Bored chemist on 16/04/2011 16:19:03

There are a fair few isotopes with half lives longer than uranium.
50vanadium with a half life of 1.5X10^17 years for example.
I think Bismuth 1.9X10^19 years is a contender for the longest half life by alpha decay, but there's a rather odd decay mode for tellurium 128 with a half life of about 10^24 years. Measuring half lives like that is no small challenge.

It's hard to say what the shortest half lives are because they are rather difficult to measure.
I think an astatine isotope holds the current record, about an eighth of a microsecond IIRC.