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Question
Which of the d-block elements may not be regarded as the transition elements?
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Solution
The electronic configuration of Zn, Cd and Hg is represented by the general formula (n – 1)d10ns2. In these elements, the orbitals are completely filled in the ground (normal) state as well as in ordinary oxidation states, i.e., the subshells are not incomplete in their atomic state or any one of the ionic states. Therefore, they cannot be called transition elements.
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| Column I (Property) | Column II (Metal) | |
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| upto +7 oxidation state | (c) \[\ce{Os}\] | |
| (iii) | 3d block element with highest melting point | (d) \[\ce{Fe}\] |
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| Column I (Aqueous solution of salt) |
Column II (Colour) |
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| (ii) \[\ce{NiCl2.4H2O}\] | (b) Light pink |
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| (v) \[\ce{Cu2 Cl2}\] | (e) Pink |
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| Fe3+/Fe2+ | +0.8 V |
Use this data to comment upon:
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