A nucleus `""_(11)Na^(24)` emits a `beta`-particle to change into magnesium (Mg).
What are numbers 24 and 11 called?

Explanation

To solve the question regarding the nucleus \( _{11}^{24}\text{Na} \) and what the numbers 24 and 11 represent, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Element**: The notation \( _{11}^{24}\text{Na} \) represents the element Sodium (Na).

2. **Understand the Notation**: In the notation \( _{Z}^{A}\text{X} \), where \( Z \) is the atomic number, \( A \) is the mass number, and \( \text{X} \) is the chemical symbol of the element.

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