Identify orbitals which are filled in 6th period

Options

A. 6s,4f,5d,6p
B. 6s,6p,5f,6d
C. 6s,6p,6d,6f
D. 6s,5f,6p,6d

Answer

To identify the orbitals that are filled in the 6th period of the periodic table, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Period Concept**: The 6th period corresponds to the principal quantum number \( n = 6 \). This means we are looking for orbitals where the principal quantum number is 6.

2. **Identify the Types of Orbitals**: In any period, the types of orbitals that are filled are:
- \( ns \) (s-orbital of the current period)
- \( np \) (p-orbital of the current period)
- \( (n-1)d \) (d-orbitals of the previous period)
- \( (n-2)f \) (f-orbitals of the period before the previous one)

3. **Substitute \( n = 6 \)**: Now, we substitute \( n \) with 6 in the general formula:
- \( ns = 6s \)
- \( np = 6p \)
- \( (n-1)d = 5d \)
- \( (n-2)f = 4f \)

4. **List the Orbitals**: Based on the substitutions, the filled orbitals in the 6th period are:
- \( 6s \)
- \( 6p \)
- \( 5d \)
- \( 4f \)

5. **Order the Orbitals**: The typical order of filling these orbitals is:
- \( 6s \)
- \( 4f \)
- \( 5d \)
- \( 6p \)

6. **Conclusion**: Therefore, the orbitals that are filled in the 6th period are \( 6s, 4f, 5d, \) and \( 6p \).

### Final Answer:
The orbitals filled in the 6th period are \( 6s, 4f, 5d, \) and \( 6p \).

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