`overset26 8X` atom is isotonic to `oversety 6Y` atom. The value of y is :

Options

A. 8
B. 16
C. 24
D. 32

Explanation

To solve the problem, we need to determine the atomic mass (A) of atom Y, given that atom X is isotonic to atom Y. Isotonic atoms have the same number of neutrons.

### Step-by-Step Solution:

1. **Identify the given information:**
- Atomic mass (A) of atom X = 26
- Atomic number (Z) of atom X = 8
- Atomic number (Z) of atom Y = 6

2. **Calculate the number of neutrons in atom X:**
- The number of neutrons (N) can be calculated using the formula:
\[ N = A - Z \]
- For atom X:
\[ N_X = 26 - 8 = 18 \]

3. **Since atom Y is isotonic to atom X, it must also have the same number of neutrons:**
- Therefore, the number of neutrons in atom Y (N_Y) is also 18.

4. **Set up the equation for atom Y:**
- Using the same formula for atom Y:
\[ N_Y = A_Y - Z_Y \]
- We know that \( Z_Y = 6 \) (atomic number of atom Y) and \( N_Y = 18 \):
\[ 18 = A_Y - 6 \]

5. **Solve for the atomic mass (A_Y) of atom Y:**
- Rearranging the equation gives:
\[ A_Y = 18 + 6 = 24 \]

6. **Conclusion:**
- The value of \( y \) (the atomic mass of atom Y) is 24.

### Final Answer:
The value of \( y \) is 24.

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