Question

state hunds rule,paulis exclusion principle

Answer 1

hey mate here is ur answer.

Hunds rule states that

while filling electrons in same energy orbitals fill all of them singly before pairing....

Pauli exclusion principle

two electrons in an atom cannot have same set of all 4 quantum numbers......
or

only 2 electrons can exist in same orbitals....

aufbau principles

in the ground state of the atoms the orbitals are filled in order of their increasing energies....

Answer 2

Hund's Rule. Hund's rule: every orbital in a subshell is singly occupied with one electron before any one orbital is doubly occupied, and all electrons in singly occupied orbitals have the same spin.
the assertion that no two fermions can have the same quantum number.