In which pair one has all Unpaired d orbitals while other have all paired d orbitals?
Correct answer: C. Cr and Cu
- A. Cu and Zn
- B. Cr and Fe
- C. Cr and Cu
- D. Mn and Co
Explanation
The correct answer is Cr and Cu. Chromium (Cr) has an electron configuration of [Ar] 3d5 4s1, which results in five unpaired electrons in its d orbitals. On the other hand, Copper (Cu) has an electron configuration of [Ar] 3d10 4s1, meaning all its d electrons are paired. The other options are incorrect because:Cu and Zn: Copper has unpaired electrons, and Zinc (Zn) has all paired electrons (3d10 4s2).Cr and Fe: Both Chromium and Iron have unpaired d electrons; Chromium has five unpaired and Iron has four unpaired.Mn and Co: Both Manganese and Cobalt have unpaired d electrons; Manganese has five unpaired and Cobalt has three unpaired.Thus, Cr and Cu is the only correct pair with one element having all unpaired d orbitals and the other all paired.
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About Transition Elements
Transition elements are identified by their partially filled d subshells in atoms or common ions. The topic covers the electronic structure of d-block elements, including the filling order of 4s and 3d orbitals, variable oxidation states and the distinction between transition elements and elements with completely filled d subshells.
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