Question 1

Which process decreases the atomic number by one while keeping the mass number unchanged?

Accepted Answer

Electron capture

Question 2

Given the electron capture of $$^{81}\mathrm{Kr}$$, what is the identity of the daughter nuclide?

Accepted Answer

$$^{81}\mathrm{Br}$$

Question 3

Which of the following best describes the effect of positron emission on the nucleus?

Accepted Answer

The atomic number decreases by one.

Question 4

A nuclide of $$^{82}\mathrm{Sr}$$ undergoes positron emission. What is the resulting daughter nuclide?

Accepted Answer

$$^{82}\mathrm{Rb}$$

Question 5

Which of the following nuclear reactions represents electron capture?

Accepted Answer

$$^{81}\mathrm{Kr} + e^- \$$rightarrow ^{81}$$\mathrm{Br}$$

Question 6

If a nuclide is above the band of stability, which process is most likely to occur to restore stability?

Accepted Answer

Electron capture or positron emission

Question 7

Which of the following statements about the neutron-to-proton ratio is correct?

Accepted Answer

Nuclides above the band of stability tend to undergo electron capture or positron emission.

Question 8

Which of the following is the correct equation for the positron emission of $$^{82}\mathrm{Sr}$$?

Accepted Answer

$$^{82}\mathrm{Sr} \$$rightarrow ^{82}$$\mathrm{Rb} + e^+$$

Question 9

A radioactive isotope undergoes electron capture. Which of the following changes occurs in the nucleus?

Accepted Answer

A proton is converted into a neutron.

Question 10

Which of the following best explains why positron emission and electron capture both move a nuclide toward the band of stability?

Accepted Answer

Both processes increase the neutron-to-proton ratio.

Question 11

A sample of $$^{81}\mathrm{Rb}$$ undergoes electron capture. What is the resulting daughter nuclide?

Accepted Answer

$$^{81}\mathrm{Kr}$$

Question 12

Which of the following is a correct description of positron emission?

Accepted Answer

A proton is converted into a neutron.

Question 13

If $$^{81}\mathrm{Kr}$$ undergoes positron emission, what is the resulting nuclide?

Accepted Answer

Question 14

Which of the following nuclear reactions is an example of electron capture?

Accepted Answer

$$^{81}\mathrm{Rb} + e^- \$$rightarrow ^{81}$$\mathrm{Kr}$$

Question 15

A nuclide with too many protons relative to neutrons will most likely undergo which process?

Accepted Answer

Positron emission

Band of Stability: Electron Capture and Positron Emission

Study Guide - Practice Questions