The pair of atoms having the same number of neutrons is

Options

A. `""_(6)^(12)C, ""_(12)^(24)Mg`
B. `""_(11)^(23)Na, ""_(9)^(19)F`
C. `""_(11)^(23)Na, ""_(12)^(24)Mg`
D. `""_(11)^(23)Na, ""_(19)^(39)K`

Explanation

To determine which pair of atoms has the same number of neutrons, we need to follow these steps:

### Step-by-Step Solution:

1. **Understand the Concept of Neutrons**:
- The number of neutrons in an atom can be calculated using the formula:
\[ \text{Number of Neutrons} = \text{Atomic Mass} - \text{Atomic Number} \]

2. **Identify the Atoms in Each Option**:
- Let's analyze the pairs of atoms given in the options.

3. **Calculate Neutrons for Each Pair**:
- **Option A**:
- Carbon (\(^{12}_{6}C\)):
- Atomic Mass = 12, Atomic Number = 6
- Neutrons = \(12 - 6 = 6\)
- Magnesium (\(^{24}_{12}Mg\)):
- Atomic Mass = 24, Atomic Number = 12
- Neutrons = \(24 - 12 = 12\)
- **Result**: Not the same (6 ≠ 12).

- **Option B**:
- Sodium (\(^{23}_{11}Na\)):
- Atomic Mass = 23, Atomic Number = 11
- Neutrons = \(23 - 11 = 12\)
- Fluorine (\(^{19}_{9}F\)):
- Atomic Mass = 19, Atomic Number = 9
- Neutrons = \(19 - 9 = 10\)
- **Result**: Not the same (12 ≠ 10).

- **Option C**:
- Sodium (\(^{23}_{11}Na\)):
- Neutrons = \(23 - 11 = 12\)
- Magnesium (\(^{24}_{12}Mg\)):
- Neutrons = \(24 - 12 = 12\)
- **Result**: Same (12 = 12).

- **Option D**:
- Sodium (\(^{23}_{11}Na\)):
- Neutrons = \(23 - 11 = 12\)
- Potassium (\(^{39}_{19}K\)):
- Atomic Mass = 39, Atomic Number = 19
- Neutrons = \(39 - 19 = 20\)
- **Result**: Not the same (12 ≠ 20).

4. **Conclusion**:
- The only pair of atoms that has the same number of neutrons is found in **Option C**: Sodium and Magnesium, both having 12 neutrons.

### Final Answer:
The pair of atoms having the same number of neutrons is **Option C: Sodium and Magnesium**.