Electron enters the sub-shell for which (n+l) value is minimum. This is enunciated as

Name the sub-shell if l = O.

Name the sub-shell if l = 2.

Electrons occupy the available sub-level which has lower n+l value. This is called:

The (n + l) value for 4f-sub shell is

The seqence of filling electgron in sub-shells of element with few exception in d-block and f-block element is govened by.Aufbau principle followed by Hund's rule and pauli's ecxclusion principal a. The electron prefers to enter into sub-shell with lower (n +l) values The energy for any sub-shell of an element other than hydrogen is praportioanal to the sum of principal quantum number (n) and angular momentum quantum number b. If (n + l) value is same for many sub-shell with lowest n value c. i. Fulfiling sub-shell is more stable ii. Half filled sub-shell is more stable less than half filed Which pair of sub-shell has same energy for above described excriptional element under rule (a) ?

The sub shells present in L shell are

The sub-shell that is not present in L orbit

The two electrons in K sub-shell will differ in