Chemistry Transition Elements MDCAT 2016
PMDC Verified Question 58 of 68
Which element of 3-d series of periodic table shows the electronic configuration of \(3d^{8} , 4s^{2}\)?
A
Copper
B
Zinc
C
Cobalt
D
Nickel
Tap any option to test your recall and reveal the step-by-step Propolis autopsy.

Propolis Cognitive Error Autopsy

Official Correct Choice:
Option D: Nickel
Concept:

The atomic number can be determined by adding the number of core electrons to the valence electrons shown in the configuration.

Solution:

  • The configuration provided is \([Ar] \; 3d^8 \; 4s^2\).


  • Argon core (\(Ar\)) = 18 electrons.


  • Valence electrons = \(8 + 2 = 10\) electrons.


  • Total atomic number (\(Z\)) = \(18 + 10 = 28\).


  • Looking at the 3d transition series, atomic number 28 corresponds to Nickel (Ni).


Why other options are incorrect:

  • Copper is \(Z=29\) (\(3d^{10} \; 4s^1\)).


  • Zinc is \(Z=30\) (\(3d^{10} \; 4s^2\)).


  • Cobalt is \(Z=27\) (\(3d^7 \; 4s^2\)).

Quality & Fidelity Assurance: Every question on BeambePrep is rigorously curated against the official PMDC syllabus with zero filler, zero out-of-syllabus content, and zero typos. When an authentic past paper originally contained a historical mistake or ambiguity from the examining board (such as UHS or NUMS), BeambePrep faithfully reflects the original paper while detailing the nuance and scientific consensus in the autopsy above.

Previous Question All Transition Elements MCQs Next Question

Want to solve full-length papers under timed exam conditions?

Practice with zero-scroll lockdown sprints, dynamic latency zone timers, live peer selection telemetry, and the automated Amber mistake recovery loop.

Enter Arena Sprint iOS App Android App