Question

How many electrons are in the n = 2 orbit
A: 2
B: 8
C: 18
D: 7

Answer 1

The first shell has 2 electrons( Hydrogen and Helium )
The 2nd has: 2+6=8
The 3rd has: 2+6+12=20
The 4th has: 2+6+12+20=40
:)

Answer 2

Option B: 8

Step-by-step explanation:

Given:

n = 2

'n' mentioned here defines, principle quantum number.

Principle quantum number is used to represent principle energy shell in which electron revolves around nucleus.

Value of n = 1, 2, 3, 4, .........

No. of electron in any principle energy shell =
`2n^2`

n = 2

`No.\ of\ electron = 2 (2)^2=2* 4\\=8`

Among given options, option b is correct.