Question 1

Which of the following statements best distinguishes a chemical reaction from a nuclear reaction?

Accepted Answer

Nuclear reactions involve changes in the nucleus, while chemical reactions involve changes in the electron cloud.

Question 2

Which type of radiation has the highest ionizing power but the lowest penetrating power?

Accepted Answer

Alpha particles

Question 3

What is the daughter nuclide produced when $$^{209}_{83}\mathrm{Bi}$$ undergoes alpha decay?

Accepted Answer

$$^{205}_{81}\mathrm{Tl}$$

Question 4

Which of the following nuclear equations correctly represents beta decay?

Accepted Answer

$$^{14}_{6}\mathrm{C} \$$rightarrow ^{14}$$_{7}\mathrm{N} $$+ ^{0}$$_{-1}\mathrm{e}$$

Question 5

A radioactive isotope has a half-life of 2.0 hours. If you start with 8.0 g, how much remains after 6.0 hours?

Accepted Answer

1.0 g

Question 6

Which of the following is true about gamma emission?

Accepted Answer

It does not change either the atomic number or the mass number.

Question 7

Which process is responsible for the energy produced by the sun?

Accepted Answer

Nuclear fusion

Question 8

What particle is emitted during the radioactive decay of $$^{22}_{11}\mathrm{Na} to$$ $$^{22}_{10}\mathrm{Ne}$$?

Accepted Answer

$$^{0}_{-1}\mathrm{e} ($$beta particle)

Question 9

Which of the following best describes positron emission?

Accepted Answer

A proton is converted into a neutron, and a positron is emitted.

Question 10

Which device is based on the ability of radioactive rays to ionize matter?

Accepted Answer

Geiger-Muller counter

Question 11

If the rate constant $$k$$ for a radioactive decay is $$0.231\ \mathrm{yr}^{-1}$$, what is the half-life $$t_{1/2}$$?

Accepted Answer

$$t_{1/2} = \frac{0.693}{0.231} = 3.00\ \mathrm{yr}$$

Question 12

Which of the following statements about nuclear fission and fusion is correct?

Accepted Answer

Both fission and fusion release energy, but fusion releases more energy per gram.

Question 13

A radiotracer used in PET scans emits which type of particle?

Accepted Answer

Positron

Question 14

Which of the following is a correct nuclear equation for electron capture?

Accepted Answer

$$^{40}_{19}\mathrm{K} $$+ ^{0}$$_{-1}\mathrm{e} \$$rightarrow ^{40}$$_{18}\mathrm{Ar}$$

Question 15

Which of the following nuclides is radioactive based on its number of protons?

Accepted Answer

$$^{210}_{84}\mathrm{Po}$$

Question 16

A 1.35 mg sample of $$^{236}\mathrm{Pu}$$ has a half-life of 2.86 years. How much remains after 5.00 years?

Accepted Answer

0.36 mg

Question 17

Which of the following best describes the process of transmutation?

Accepted Answer

A nucleus changes into a different element by changing its number of protons.

Question 18

Which of the following is a real-world application of radioactivity in medicine?

Accepted Answer

Using radiotracers to monitor organ function in PET scans

Question 19

Which of the following is true about the conservation laws in nuclear equations?

Accepted Answer

The sum of the atomic numbers and mass numbers must be equal on both sides.

Chapter 21: Radioactivity and Nuclear Chemistry – Study Notes

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