Concept Used:
For a given principal quantum number n, the azimuthal quantum number l can have values:
l = 0 to (n − 1)
Orbital notation:
s → l = 0
p → l = 1
d → l = 2
f → l = 3
g → l = 4
Step 1: Condition for g-orbital
For a g-orbital, l = 4
Thus,
n − 1 ≥ 4
Step 2: Find the lowest value of n
n ≥ 5
Final Answer:
The lowest value of principal quantum number that allows g-orbitals to exist is:
n = 5