/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Q.58 The plutonium isotope 239 Pu has... [FREE SOLUTION] | 91Ó°ÊÓ

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The plutonium isotope 239 Pu has a half-life of 24,000 years and decays by the emission of a 5.2 MeV alpha particle. Plutonium is not especially dangerous if handled because the activity is low and the alpha radiation doesn’t penetrate the skin. However, there are serious health concerns if even the tiniest particles of plutonium are inhaled and lodge deep in the lungs. This could happen following any kind of fire or explosion that disperses plutonium as dust. Let’s determine the level of danger.

Short Answer

Expert verified

The unstable nuclei undergo radioactive decay. We can predict the decay pattern. the number of left(N)

Step by step solution

01

Determinate using exponential decay equation

N=Noe-tt

Here the number of atoms at the time

N=No2ast→t12Theequation(1)canalsobewrittenintermsofhalflifetimeN=No12tt12

02

The number of decay per second of the radioactive sample is know as activity(R)

R=Ro12dtHere,theactivityatthetimet=0isRoRo=rNotheequationfor,R=tn2t12Inthisproblemwewillevaluate

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