Which of the following orbitals is the last to fill?
A.
1s
B.
3s
C.
4p
D.
6s
To determine which orbital is the last to fill, you need to consider the order of orbital filling based on the Aufbau principle, which states that electrons fill orbitals starting from the lowest energy level to the highest.
Here is the typical order in which orbitals are filled:
- 1s
- 2s
- 2p
- 3s
- 3p
- 4s
- 3d
- 4p
- 5s
- 4d
- 5p
- 6s
- 4f
- 5d
- 6p
Explanation:
- A. 1s: This is the first orbital to fill, as it is the lowest energy orbital.
- B. 3s: This orbital is filled after 2p and before 4p.
- C. 4p: This orbital is filled after 3s and before 5s.
- D. 6s: This orbital is filled after 5p and before 4f.
Final Answer:
D. 6s
The 6s orbital is the last to fill among the given options.