The total number of subshells in fouth energy level of an atom is

Options

A. 4
B. 8
C. 16
D. 32

Answer

To determine the total number of subshells in the fourth energy level of an atom, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Energy Level (n)**:
The fourth energy level corresponds to \( n = 4 \).

2. **Determine the Azimuthal Quantum Number (l)**:
The azimuthal quantum number \( l \) can take values from \( 0 \) to \( n-1 \). Therefore, for \( n = 4 \):
\[ l = 0, 1, 2, 3 \]

3. **Assign Subshells to Quantum Numbers**:
Each value of \( l \) corresponds to a specific subshell:
- \( l = 0 \) corresponds to the s subshell
- \( l = 1 \) corresponds to the p subshell
- \( l = 2 \) corresponds to the d subshell
- \( l = 3 \) corresponds to the f subshell

4. **Count the Total Subshells**:
From the values of \( l \) we identified:
- \( l = 0 \) (s)
- \( l = 1 \) (p)
- \( l = 2 \) (d)
- \( l = 3 \) (f)

Thus, the total number of subshells in the fourth energy level is:
\[ \text{Total subshells} = 4 \quad (\text{s, p, d, f}) \]

5. **Conclusion**:
Therefore, the total number of subshells in the fourth energy level of an atom is **4**.

### Final Answer:
The total number of subshells in the fourth energy level of an atom is **4**.

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