The disintegration of an isotope of sodium `._(11)Na^(24) rarr ._(12)Mg^(24) + ._(-1)e^(0)` shown is due to

Options

A. The emission of `beta-`radiation
B. The formation of a stable nuclide
C. The fall in the neutron : proton ratio
D. None of these

Explanation

To solve the question regarding the disintegration of the isotope of sodium, \( _{11}^{24}\text{Na} \), we need to analyze the given nuclear reaction:

\[ _{11}^{24}\text{Na} \rightarrow _{12}^{24}\text{Mg} + _{-1}^{0}\text{e} \]

### Step-by-Step Solution:

1. **Identify the Reaction Type**:
The reaction shows sodium-24 transforming into magnesium-24 and emitting a beta particle (\( _{-1}^{0}\text{e} \)). This indicates that the sodium nucleus is undergoing beta decay.

2. **Understand Beta Decay**:
In beta decay, a neutron in the nucleus is transformed into a proton, emitting a beta particle (an electron) in the process. This results in an increase in the number of protons and a decrease in the number of neutrons.

3. **Analyze the Nucleon Count**:
- Sodium-24 has 11 protons and 13 neutrons (since \( 24 - 11 = 13 \)).
- After the decay, magnesium-24 has 12 protons and 12 neutrons (since \( 24 - 12 = 12 \)).
- The transformation from sodium to magnesium involves the conversion of one neutron into one proton, which is consistent with the emission of a beta particle.

4. **Proton-Neutron Ratio**:
The initial proton-neutron ratio for sodium-24 is \( \frac{11}{13} \), which is less than 1. After the decay, the ratio for magnesium-24 becomes \( \frac{12}{12} = 1 \). This change indicates a more stable configuration, as stable nuclei tend to have a proton-neutron ratio closer to 1.

5. **Conclusion**:
The disintegration of sodium-24 is due to the emission of beta radiation, which is a common process for isotopes that have an unfavorable proton-neutron ratio. The decay results in the formation of a more stable nucleus (magnesium-24).

### Final Answer:
The disintegration of the isotope \( _{11}^{24}\text{Na} \) is due to the emission of beta radiation.