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The d & f Block Elements — Chemistry STD 12 Science — Question

Bihar BoardEnglish MediumSTD 12 ScienceChemistryThe d & f Block Elements3 Marks
Question
How would you account for the following:
There is a gradual decrease in the atomic sizes of transition elements in a series with increasing atomic numbers.
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Answer

There is a gradual decrease in the atomic sizes of transition elements in a series with increasing atomic numbers due to poor shielding effect of d-electrons, the net electrostatic attraction between the nucleus and the outermost electrons increases.

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