As Principle Quantum Number is 7, so the number of Azimuthal Quantum Numbers for this energy level is calculated by following formula,
l = n - 1
As, n=7
So,
l = 7 - 1
l = 6
So, n=7 contains 1, 2, 3, 4, 5 and 6 Sub-Shells.
Number of Electrons in Subshells,
Number of electrons in each subshell is calculated by following formula,
2 (2l + 1)
As, l=1 (given),
So, 2 (2(1) + 1)
2 (2 + 1)
2 (3)
6
Result:
The number of electrons in n=7 and l=1 are 6.