Write nuclear equations for the beta decay of (a) \({ }_{13}^{28} \mathrm{Al}\) (b) \({ }_{93}^{239} \mathrm{~Np}\)

Beta decay is a type of radioactive decay where a neutron inside an atomic nucleus transforms into a proton and an electron. This means the element changes because the atomic number increases by 1, but the mass number stays the same. The emitted electron is called a beta particle, symbolized as \(\beta^-\).
This process also releases a very tiny particle with hardly any mass, called an antineutrino, symbolized as \(\bar{u}_e\). Beta decay is important because it shows how some elements can change into different elements naturally over time.

Nuclear equations help us understand and describe beta decay in a structured way.
They follow certain rules to make sure everything balances out.
One key rule is that the sum of atomic numbers and the sum of mass numbers must be the same on both sides of the equation.
Let's look at the beta decay of aluminum-28. Starting with \({ }_{13}^{28} \text{Al}\), the equation would be: \[ { }_{13}^{28} \text{Al} \rightarrow { }_{14}^{28} \text{Si} + \beta^- + \bar{u}_e \]
Here, aluminum becomes silicon because the atomic number goes up from 13 to 14, but the mass number stays the same at 28.
Now, let's see the beta decay for neptunium-239: \[ { }_{93}^{239} \text{Np} \rightarrow { }_{94}^{239} \text{Pu} + \beta^- + \bar{u}_e \]
Here, neptunium turns into plutonium because its atomic number increases from 93 to 94, while the mass number remains at 239.
By writing nuclear equations like these, we can clearly show what happens during the process of beta decay.

To understand beta decay, we need to know about atomic structure.
An atom consists of three main particles: protons, neutrons, and electrons.

• Protons have a positive charge.
• Neutrons have no charge.
• Electrons have a negative charge.

The protons and neutrons are in the nucleus at the center of the atom, while the electrons orbit around the nucleus.
In beta decay, a neutron in the nucleus changes into a proton and an electron (beta particle). This changes the element because the number of protons defines what element the atom is.

Radioactivity is the process by which unstable atomic nuclei lose energy by emitting radiation.
This can happen in several ways, including beta decay. When an atom undergoes beta decay, it releases a beta particle (electron) and an antineutrino.

• These emissions are forms of radiation.
• Radioactivity helps us understand how elements can transform naturally over time.

Studying radioactivity is important for several reasons.

• It's crucial in nuclear medicine for treating and diagnosing diseases.
• In geology, it helps date ancient rocks.
• It's critical in nuclear power generation.

Knowing about radioactivity gives us a deeper understanding of natural processes and helps us harness them for practical uses.