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Question
Compare the general characteristics of the first series of the transition metals with those of the second and third series metals in the respective vertical columns. Give special emphasis on the following point:
Atomic sizes
Solution
Generally, ions or atoms of the same charge in a series show a gradual decrease in radii with increasing atomic number, although this decrease is very small. But the size of atoms of 4d series is larger than the corresponding elements of 3d series, while the size of the corresponding elements of 5d series is almost the same. The reason for this is lanthanoid contraction.
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| Column I (Aqueous solution of salt) |
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