MDCAT Chemistry — Transition Elements
Transition Elements is a core Chemistry topic in the PMDC MDCAT syllabus, covering 2 subtopics. Below are the subtopics to revise, how often the topic appears in past papers, and real past-paper MCQs to try.
Subtopics (2)
- Chelates and Complex Ions
- Electronic Structure of d-block
How Transition Elements is tested
Across the 16 MDCAT past papers on ParhaiKrlo, Transition Elements accounts for 18 questions. It appears in 12 of them, about 1.5 questions a paper. The heaviest was MDCAT 2024, with 2 questions.
| Paper | Questions |
|---|---|
| MDCAT 2024 | 2 |
| MDCAT 2023 | 2 |
| MDCAT 2022 | 1 |
| MDCAT 2019 | 2 |
| MDCAT 2018 | 1 |
| MDCAT 2016 | 2 |
| MDCAT 2015 | 1 |
| MDCAT 2013 | 2 |
| MDCAT 2012 | 2 |
| MDCAT 2011 | 1 |
| MDCAT 2009 | 1 |
| MDCAT 2008 | 1 |
Transition Elements MCQs from the MDCAT past papers
Try each one before opening the answer. Each comes with a short explanation.
- Q1 · MDCAT 2024 · Transition Elements
Electronic configuration of chromium (Proton number 24) is:
- A.[Ar]3d⁴ 4s²
- B.[Ar]3d⁵ 4s²
- C.[Ar]3d⁵ 4s¹
- D.[Ar]3d⁶ 4s²
Show answer
Answer: C. [Ar]3d⁵ 4s¹ — Chromium's electron configuration is the exception [Ar]3d5 4s1, not the expected [Ar]3d4 4s2.
- Q2 · MDCAT 2023 · Transition Elements
Which of the following transition metals shows 3d⁵ configuration in its +2 oxidation state?
- A.Cu²⁺
- B.Fe²⁺
- C.Mn²⁺
- D.Zn²⁺
Show answer
Answer: C. Mn²⁺ — Mn²⁺ has the 3d⁵ configuration among these +2 transition metal ions.
- Q3 · MDCAT 2022 · Transition Elements
In which pair one has all Unpaired d orbitals while other have all paired d orbitals ?
- A.Cu and Zn
- B.Cr and Fe
- C.Cr and Zn
- D.Mn and Co
Show answer
Answer: C. Cr and Zn — Cr has all unpaired d-electrons (d5, all 5 singly occupied), while Zn has all paired d-electrons (d10, fully filled).