Chapter 42: Q 9 Conceptual Question (page 1235)

The three isotopes

Po212,Cs137,andSr90decay asPo212Pb208+α,Cs137Ba137+e-+γ,andSr90Y90+e-Which of these isotopes would be most useful as a biological tracer? Why?

Short Answer

Expert verified

Thus,Cs137 would be quite valuable.

Step by step solution

01

Given information

Three isotopes are given:

Po212,Cs137,andSr90decay asPo212Pb208+α,Cs137Ba137+e-+γ,andSr90Y90+e-

02

Explanation

Because a gamma ray is emitted after beta decay, Cs137would be quite valuable. Because alphas and betas do not penetrate material well, they would not be discovered if they were to escape the body.

03

Explanation

However, the gamma ray does enter material well and might be identified if it were to escape the body.

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