Strontium: Isn't it Radioactive?

Nathan · #1 04/07/2006, 09:09 AM

I do remember hearing about Strontium during the Chernobyl nuclear accident in the 80's. But maybe we are using a different isotope of Stronium that is not radioactive in our tanks. I am not really too well versed in that part of chemistry, but it would be interesting to know more about how Strontium works.

-Nathan

Randy Holmes-Farley · #2 04/07/2006, 09:17 AM

There are different isotopes of strontium. The normal ones in seawater are not radioactive. They vary with different numbers of neutrons in the nucleus.

The isotopes and percentage in seawater are:

Sr88 82.56%
Sr86 9.86%
Sr87 9.02%
Sr84 0.56%

The primary radioactive one is Sr90.
It has a half life of 28 years.

capt. insano · #3 04/07/2006, 10:12 AM

I was wondering why I was growing that pesky 6th finger and tail!!

Nathan · #4 04/07/2006, 10:24 AM

Ahhhh... thanks for the refresher. It's amazing what one small change to an atom can do!

capt. insano,

Randy Holmes-Farley · #5 04/07/2006, 10:26 AM

Happy Reefing.

spidey07 · #6 04/07/2006, 01:34 PM

Quote:

Originally posted by Randy Holmes-Farley
There are different isotopes of strontium. The normal ones in seawater are not radioactive. They vary with different numbers of neutrons in the nucleus.

The isotopes and percentage in seawater are:

Sr88 82.56%
Sr86 9.86%
Sr87 9.02%
Sr84 0.56%

The primary radioactive one is Sr90.
It has a half life of 28 years.

28 years!

Yikes. sounds like some dangerous stuff. spitting out particles left and right.

Nathan · #7 04/07/2006, 02:08 PM

If the half life is 28 years, then it must only be spitting out a very tiny amount of radiation, right? I would think that the shorter the half-life, the more dangerous because it "spits out particles" at a much faster rate.

Am I on the right track or am I totally wrong?

-Nathan

spidey07 · #8 04/08/2006, 01:00 PM

nathan,

It's been a long time since chemistry so hopefully Randy can correct me...

A half-life of 28 years is VERY short. Many other elements are in the 10s of thousands of years. The very heavy radioative elements like plutonium and uranium have relatively short half lifes under 100 years depending on the isotope (number of neutrons in the nuclues)

so having such a short half-life means it is spitting out particles at a rate greater than something with a "longer" half-life. these particles/waves are termed alpha, beta and gamma radiation. I forget which ones are really bad. I think alpha can penetrate inches of lead.

All elements go through radioactive decay AFAIK.

I hope I didn't muck up the facts too much.

Randy Holmes-Farley · #9 04/08/2006, 03:39 PM

While generally true that the longer the half life the less radiation, it also depends on how much of the actual radioisotope you have to begin with. A small amount (in grams or teaspoons) can still be incredibly radioactive and deadly.