21. Nuclear Chemistry

Rate of Radioactive Decay

21. Nuclear Chemistry

# Rate of Radioactive Decay

1

concept

## Radioactive Integrated Rate Law

3m

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2

example

## Rate of Radioactive Decay Example

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3

Problem

ProblemFor the radioactive decay of lead-202 the decay constant is 1.32 x 10^{-5} yr^{-1}. How long will it take in hours to decrease to 53% of its initial amount?

A

5.72 x 10

^{4}hrsB

5.01 x 10

^{9}hrsC

4.81 x 10

^{4}hrsD

4.21 x 10

^{8}hrs4

Problem

ProblemDuring World War I radium-226 was used in the manufacturing of luminous paint. If it takes 2.12 x 10^{4} days for its degradation to be 2.49% complete, what is its decay constant?

A

1.74 x 10

^{–4}days^{–1}B

1.08 x 10

^{–5}days^{–1}C

1.19 x 10

^{–6}days^{–1}D

2.14 x 10

^{–5}days^{–1}5

Problem

ProblemIf the decay constant for polonium-209 is 6.80 x 10^{-3} ys^{-1}, what fraction of it remains after 1.1 x 10^{4} years?

A

9.00 x 10

^{–30}B

3.27 x 10

^{–33}C

8.24 x 10

^{–42}D

9.13 x 10

^{–43}Additional resources for Rate of Radioactive Decay

PRACTICE PROBLEMS AND ACTIVITIES (62)

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