Question

The $71^{st}$ electron of an element $X$ with an atomic number of $71$ enters into the orbital :

• A. $4f$
• B. $6p$
• C. $6s$
• D. $5d$

Answer 1

Answer: (D)

$5d$

Answer 2

Electronic Configuration of Element X with atomic number 71 is $[ Xe ] 4 f ^{14} 6 s ^{2} 5 d ^{1}$. The Last electron will enter in $5 d$ orbital.