The question is incomplete:
Complete question is attached below:
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Answer 1:
In the first case, two electrons in the 1st 2p sub-shell has both the electrons with same electron spin. This is a violation of Pauli's exclusion principle, according to which, orbital can contain a maximum of only two electrons, the two electrons must have opposing spins.
Answer 2:
In the second case, 3s and 3p orbital is incompletely filled. This is a violation of Hund's rule. According to Aufbau Principle, orbitals of lower energy get filled first and than orbital of higher energy. Hence, in present case, 3s orbital must be completely filled first and then electron must 3p orbital.
Answer 3:
In the 3rd case, the first sub-shell of 2p orbital has two electrons, while all other sub-shell is empty. This is a violation of Hund's rule, according to which all orbitals will be singly occupied before any is doubly occupied. Hence, in present case, there should be one electron present in each sub-shell of 2p orbital.
Answer 4:
In the forth case, 4s and 4p orbital are filled first and 3d orbital is filled. This is a violation of Aufbua principle. Because, according to Aufbua principle orbital of lower energy are filled first. In present case, 3d orbital has lower energy as compared to 4s and 4p orbital.
