- #1

Chijioke

- 14

- 3

- Homework Statement
- Is shell number same as energy level

- Relevant Equations
- The maximum number of electron per shell is given as $$2(n^2)$$ where n is energy level number. And energy level is same as electron shell.

Looking at Cacium for th electron arrangements according to shell numbers is 2, 8,8,2 since Cacium have four shells.

Going by the formula

1st shell has:$$2n^2=2\times 1^2= 2 ~electrons $$

2nd shell has:$$2n^2=2\times 2^2= 8 ~electrons $$

3rd shell has:$$2n^2=2\times 3^2= 18 ~electrons $$

But unfortunately, Cacium has only twenty electrons.

I am thinking that the remaining 10 electrons should go into the 3rd energy level. But if that happens then Cacium would not be fit to still remain in period 4.

So why is the electron filling per shell for Cacium 2,8,8,2 and not 2,8,10 according to the formula giving for the maximum number of electron that can be found in a shell?

Thank you.

Going by the formula

1st shell has:$$2n^2=2\times 1^2= 2 ~electrons $$

2nd shell has:$$2n^2=2\times 2^2= 8 ~electrons $$

3rd shell has:$$2n^2=2\times 3^2= 18 ~electrons $$

But unfortunately, Cacium has only twenty electrons.

I am thinking that the remaining 10 electrons should go into the 3rd energy level. But if that happens then Cacium would not be fit to still remain in period 4.

So why is the electron filling per shell for Cacium 2,8,8,2 and not 2,8,10 according to the formula giving for the maximum number of electron that can be found in a shell?

Thank you.