MHT CET202619 April 2026Morning ShiftChemistryd and f Block ElementsActual
Identify general electronic configuration exhibited by 2^ nd series of transition elements.
Options
- A[ Ar ] 4d¹⁻¹⁰ 4s^2
- B[ Kr ] 4d¹⁻¹⁰ 5s⁰⁻²
- C[ Xe ] 4d¹⁻¹⁰ 4s^2
- D[ Rn ] 4d¹⁻¹⁰ 6s^2
Correct answer
B. [ Kr ] 4d¹⁻¹⁰ 5s⁰⁻²
Step-by-step solution
The second series of transition elements is the 4d series, which starts from Yttrium ( Z=39 ) and ends at Cadmium ( Z=48 ). The noble gas preceding this series is Krypton ( [ Kr ] , Z=36 ). The valence electrons are filled in the 4d and 5s subshells. Due to anomalous configurations (for example, Palladium has the configuration [ Kr ] 4d¹⁰ 5s^0 and elements like Silver have [ Kr ] 4d¹⁰ 5s^1 ), the number of electrons in the 5s orbital can be 0 , 1 , or 2 . Thus, the general electronic configuration of the 2^ nd tran