$\beta+$ decay of ${ }^{22} Na$
Answer (1)
β + decay involves the transformation of a proton into a neutron, emitting a positron and an electron neutrino.
The parent nucleus, 22 N a , has an atomic number of 11 and a mass number of 22.
The daughter nucleus is 22 N e , with an atomic number of 10 and a mass number of 22.
The balanced nuclear equation for the β + decay of 22 N a is: 11 22 N a → 10 22 N e + e + + n u e .
Explanation
Understanding Beta Plus Decay The problem asks us to describe the β + decay of 22 N a . In β + decay, a proton in the nucleus is converted into a neutron, a positron ( e + ), and an electron neutrino ( n u e ). The positron is emitted from the nucleus. The mass number (A) remains the same, but the atomic number (Z) decreases by 1.
Identifying the Parent Nucleus We start with the parent nucleus, which is Sodium-22 ( 22 N a ). Sodium has an atomic number of 11.
Determining the Daughter Nucleus During β + decay, the atomic number decreases by 1, so the daughter nucleus will have an atomic number of 10. The mass number remains the same at 22. The element with atomic number 10 is Neon (Ne). So, the daughter nucleus is Neon-22 ( 22 N e ).
Writing the Nuclear Equation Now, we can write the nuclear equation for the β + decay of 22 N a :
11 22 N a → 10 22 N e + e + + n u e
Identifying the Components In this equation:
11 22 N a is the parent nucleus (Sodium-22).
10 22 N e is the daughter nucleus (Neon-22).
e + is the positron.
n u e is the electron neutrino.
Examples
Beta plus decay has applications in medical imaging, specifically in Positron Emission Tomography (PET) scans. In PET scans, a radioactive tracer that undergoes beta plus decay is introduced into the body. As the tracer decays, it emits positrons. These positrons annihilate with electrons in the body, producing gamma rays that are detected by the PET scanner. By analyzing the detected gamma rays, doctors can create detailed images of organs and tissues, helping to diagnose diseases such as cancer, heart disease, and neurological disorders. The use of specific tracers allows doctors to target particular biological processes or areas of the body, providing valuable diagnostic information.
