Sciencemadness Discussion Board

Potassium chloride going purple in radiation

Neme - 12-6-2016 at 04:25

Hi everyone,
I just read something about potassium chloride usage in dosimeters. It's based on it's ability to go from colorless to purple in radiation.

I wanted to ask if I can use just americium with beta (β-) decay to "color" it.

If not, could uranyl chloride or thorium do the work?

Maybe I could take it to hospital to x-ray. Would this work?

hyfalcon - 12-6-2016 at 07:40

Set it on a stack of KCl softner salt for about an hour or stack bags up around your experiment.

unionised - 12-6-2016 at 08:30

Americium thorium and uranium are alpha emitters, rather than beta (at least, fr the isotopes you can get hold of easily).
It's possible that teh Xray source in a hospital would be able to produce this effect. I suspect not- they are not very intense
Perhaps if you exposed it for long enough but that would either mean running the machine (expensively) without a patient, or it would need the machine to be re-calibrated for the presence of the KCl.

In any event, a bag of powdered stuff will still look white- even if it's actually discoloured.

If you could get a decent sized single crystal of KCl and put it inside the shielding on an Xray machine you might , eventually, get some discolouration.

Slightly more realistically, you might try the linear accelerators sometime used for cancer therapy.
Unlike normal Xray machines, those are designed to deliver enough energy to cause damage.

Neme - 12-6-2016 at 09:34

Well I grew up few colorless monocrystals to try this out and I'm pretty sure that americium I have access to emits beta minus.

unionised - 12-6-2016 at 09:55

I doubt it.
According to this
which says "Nineteen radioisotopes of americium have been characterized, with the most stable being 243Am with a half-life of 7,370 years, and 241Am with a half-life of 432.2 years. All of the remaining radioactive isotopes have half-lives that are less than 51 hours"
so you must have 243 or 241 and those are both alpha emitters

Neme - 12-6-2016 at 11:14

Seems like reasonable argument, I'll check it and then I will tell you.