A neutral atom in the ground state has four electrons in its fifth and outermost principal energy level. What element is it?

Tin

Explanation:

Tin is an element which belongs to the carbon family in the periodic table. It lies in group 14 of the periodic table i.e. IV a.

The symbol of Tin is Sn. Tin has 50 electron in total. Its atomic number is 50. The 50 electrons of tin are divided in its five energy shells. The outer most or the valence shell contains 4 electrons in the ground state.

The number of electrons present per shell in tin is : 2, 8, 18, 18, 4.

The electronic configuration of tin is : [Kr] 4d¹⁰5s²5p²

the positions which points up in upward carbon and down in downward carbon are axial

and vice versa holds true for equatorial positions

so the correct answer with labelled diagram will be