Question

Which electron configuration represents a transition element?
A.1s22s22p3
B.1s22s22p63s23p64s23d104p4
C.1s22s22p63s2
D.1s22s22p63s23p64s23d7

Answer 1

Answer:

Its d.

Explanation:

Transition metals all have their valence electrons in the d energy level, so it suits for  D to have their location of the valence electron in the d subshell. To add, the sum is 27 electrons meaning it is the element of Cobalt(Co).

Answer 2

The correct option is D.

• Transition metals reside at period 3 of the modern periodic table.
• The elements of the first transition series have elements from Sc to Zn.
• These elements contain a 3d orbital in their valance shell.
• Thus from the above electronic configuration, only option D has 3d orbital in its valance shell.
• Thus the electronic configuration of option D represents a transition element.