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Chapter 42: Q 25 Exercise (page 1236)

Identify the unknown isotope X in the following decays.

a.Th230鈫�X+伪b.S35鈫�X+e-+谓炉c.X鈫�K40+e++谓d.Na24鈫�Mg24+e-+谓炉鈫�X+纬

Short Answer

Expert verified

Hence, the values of X are:

a.)X=Ra226b.)X=Cl35c.)X=Ca40d.)X=Mg24

Step by step solution

01

Given information

a.Th230鈫�X+伪b.S35鈫�X+e-+谓炉c.X鈫�K40+e++谓d.Na24鈫�Mg24+e-+谓炉鈫�X+纬

02

Explanation (a)

In the following decays, we need find unknown isotope X:

a.)Th230鈫�X+伪

The decay is:

Th230=X+He4X=Ra226

03

Explanation (b)

The decay is:

04

Explanation (c)

The decay is:

05

Explanation (d)

The decay is:

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Most popular questions from this chapter

The uranium isotope U238is naturally present at low levels in many soils. One of the nuclei in the decay series of U238is the radon isotope R222n, which decays by emitting a localid="1650487447445" 5.50MeValpha particle with localid="1650487458663" t1/2=3.82days. Radon is a gas, and it tends to seep from soil into basements. The Environmental Protection Agency recommends that homeowners take steps to remove radon, by pumping in fresh air, if the radon activity exceeds 4pCiperliterof air.

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a. What is the tracer鈥檚 half-life?

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