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 Principal Quantum Number (n)**:
- The principal quantum number (n) indicates the energy level of an atom. For the fourth energy level, n = 4.

2. **Determine the Azimuthal Quantum Number (l)**:
- The azimuthal quantum number (l) defines the shape of the subshells and can take values from 0 to (n-1). Therefore, for n = 4, l can take the values:
- l = 0
- l = 1
- l = 2
- l = 3

3. **Count the Number of Subshells**:
- Each value of l corresponds to a different 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
- Thus, for n = 4, we have four values of l, which means there are four subshells.

4. **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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