# Lesson Worksheet: Positron Emission Physics

In this worksheet, we will practice solving nuclear equations involving positron emission.

Q1:

The diagram shows nitrogen-13 decaying via positron emission. What isotope is produced in this process? • ANitrogen-14
• BCarbon-14
• CCarbon-13
• DOxygen-13
• ECarbon-12

Q2:

Knowing that oxygen-15 can undergo positron emission, which of the elements listed in the table does an oxygen-15 nucleus become when it undergoes positron emission?

 Element Number of Protons Boron Carbon Nitrogen Oxygen Fluorine Neon Sodium 5 6 7 8 9 10 11
• ABoron
• BNitrogen
• COxygen
• DCarbon
• EFluorine

Q3:

The following nuclear equation shows how an isotope of carbon decays to an isotope of boron via positron emission:

What is the value of in the equation?

Q4:

When an atomic nucleus emits a positron, by how much does the mass number of the remaining nucleus change?

Q5:

Which of the following statements correctly describes positron emission?

• AIf an unstable nucleus has too many neutrons, one or more neutrons will be ejected from the nucleus.
• BIf an unstable nucleus has too many nucleons, 2 protons and 2 neutrons may be ejected from the nucleus.
• CIf an unstable nucleus has too few neutrons, a proton may decay into a neutron, releasing a high-energy electron from the nucleus.
• DIf an unstable nucleus has too few neutrons, a proton may decay into a neutron, releasing a high-energy positron from the nucleus.

Q6:

The following nuclear equation shows how an isotope of strontium decays to an isotope of rubidium via positron emission:

What are the values of and in the equation?

• A,
• B,
• C,
• D,
• E,

Q7:

When an atomic nucleus emits a positron, by how much does the atomic number of the remaining nucleus change?

Q8:

Oxygen-13 decays via positron emission to nitrogen-13. Nitrogen-13 decays via positron emission to carbon-13. These statements are shown in the following nuclear equation:

What is the value of in this nuclear equation?

What is the value of in this nuclear equation?

Q9:

The graph shows an isotope of sodium decaying via positron emission. What isotope of sodium does the graph show?

• ASodium-22
• BSodium-24
• CSodium-21
• DSodium-23
• ESodium-20

What isotope of neon does the graph show?

• ANeon-24
• BNeon-20
• CNeon-23
• DNeon-21
• ENeon-22

Q10:

The following nuclear equation shows how an isotope of magnesium decays to an isotope of sodium via positron emission: What is the value of in the equation?