Consider the last electron of an element having atomic number $9$ and choose the correct option.
Show Hint
- Sum of total nodes = 1
- n = 2; l = 0
- Last electron enters in 2s subshell
There are 5e- with l = 0
The Correct Option is B
Solution and Explanation
- For the last electron, the quantum numbers are:
- The principal quantum number (\( n \)) = 2 (since it is in the second shell).
- The azimuthal quantum number (\( l \)) = 0 (since it is in an \( s \)-orbital).
Thus, the correct answer is (2) \( n = 2; l = 0 \).
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