Question

the electronic configuration
of an element is given below.
Observe it and identify. Which
principal/s is/are violated ?
Explain
1S2 , 2S2 , 2P3​

Answer 1

Answer:

the electronic configuration given is 1s2, 2s2, and 2p3.

none of the principles are violated here.

verification :

1) aufbau's principle : "the ground state of an atom or ion, electrons fill atomic orbitals of the lowest available energy levels before occupying higher levels."

here, 1s subshell is filled first and then 2s subshell is filled. and then 2p subshell is filled (half filled). So it does not violate aufbau's law of filling of electrons.

2) paul's exclusion principle :

here, no two electrons have exactly the same 4 quantum numbers. hence, it does not violate this principle.

3) hund's rule :

here, there is actually a problem. because your question doesnt specify the orbitals of 2p subshell.

now assuming that electronic configuration is 1s2, 2s2, 2px,2py,2pz,

it doesn't violate the hund's rule. as pairing of electron is only taking place in a subshell after every orbital has one electron each.

__________________