Collins wrong answer?

[dk00]

The maximum number of electrons that could be placed in the fifth shell of an atom is
A) 10 B) 18 C) 25 D) 50
Answer: D
Explanation: use 2n^2

Isn't D the number of electrons in the entire atom not just the fifth subshell? wouldnt this be B with 18 electrons in the 5th shell?

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[Ezoption]

I believe the answer would be B if the question asked how many electrons are in the 3rd shell. Since the question is asking how many electrons are in the fifth shell, the fifth shell contains 5 subshells (s,p,d,f,g) which contain a total of 25 orbitals (1+3+5+7+9) which can hold 50 electrons.

N=3
L=2(s(0),p(1),d(2))= 9 orbitals = 18 electrons

N=5
L=4(s(0),p(1),d(2),f(3),g(4))= 25 orbitals = 50 electrons

 

[dk00]

The question makes it sound like its asking about only the 5th subshell! Not the ones below it
S p d f g
9 orbitals within the fifth G subshell
18 electrons

 

[Ezoption]

The question makes it sound like its asking about only the 5th subshell! Not the ones below it
S p d f g
9 orbitals within the fifth G subshell
18 electrons

Well, the question does ask how many electrons can be placed in the fifth shell not the G subshell.

Just think about it like this.

5th shell (5s2, 5p6, 5d10, 5f14, 5g18 = 50 )<--- all these electrons are in the 5th shell
4th shell (4s2, 4p6, 4d10, 4f14 = 32)<--- all these electrons are in the 4th shell, etc...
3rd shell (3s2, 3p6, 3d10 = 18)
2nd shell (2s2, 2p6 = 8)
1st shell (1s2 = 2)