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I need to list radioactive elements and their products after nuclear decay. Are these...

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claymore | Student, Undergraduate | eNoter

Posted January 15, 2013 at 12:23 AM via web

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I need to list radioactive elements and their products after nuclear decay. Are these acceptable examples?

Uranium-238 decays into Thorium-234 and Helium-4

92238U --> 90234Th + 24He

 

Plutonium-239 decays into Uranium-235 and Helium-4

94239Pu --> 92235U + 24He

 

Radon-222 decays into Polonium-218 and Helium-4

86222Rn --> 84218Po + 24He

 

Polonium-218 decays into Lead-214 and Helium-4

84218Po à 82214Pb + 24He

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jerichorayel | College Teacher | (Level 1) Senior Educator

Posted January 15, 2013 at 10:36 AM (Answer #1)

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So far I have seen that you understand the process of alpha decay in which any radioactive element that releases an alpha particle (helium nucleus) will have its proton number subtracted by 2 and the mass number by 4. The four examples that you have written are one of the most common alpha decays that have been studied over the past years.

Let me rewrite them for you:

`92 ^(238)U -> 90 ^(234)Th + 2^(4)He`

         Half life: `4.468x10^(9) years` 

`94 ^(239)Pu -> 92 ^(235)U + 2^(4)He`

         Half life: `24100 years`

`86 ^(222)Rn -> 84^(218)Po + 2^(4)He`

         Half life: `3.8 days`

84^(218)Po -> 82^(214)Pb + 2^(4)He

         Half life: `3.10 minutes`

 

If you would consider, I have some more examples here:

 

`84^(214)Po -> 82^(210)Pb + 2^(4)He`

Half life: 0.1643 milliseconds

`84^(210) Po -> 82^(206)Pb + 2^(4)He`

Half life: 138.376 days

 

Sources:

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