Question

Question 5 a +3 cation of a certain transition metal has three electrons in its outermost d subshell. which transition metal could this be? shade all the possibilities in the periodic table outline below.

Answer 1

Chromium, molybdenum ([Kr] 4d⁵5s¹) and wolfram ([Xe] 4f¹⁴5d⁴6s²) cations have three d electrons.
₂₄Cr 1s²2s²2p⁶3s²3p⁶3d⁵4s¹.
₂₄Cr³⁺ 1s²2s²2p⁶3s²3p⁶3d³4s⁰.
This three cations (chromium, molybdenum and wolfram) lost three electrons from last s orbital, because s orbital is far away from nucleus.