What is lanthanoid contraction & what ar the consequences of lanthanoid contraction?
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Consequences of the lanthanide contraction are:
1) Resemblance of second and third transition series
The pair of the elements: Zr-Hf, Nb-Ta, Mo-W etc. posses almost same size.
2) Similarity among lanthanide:
Because of the same change in the radii their chemical properties are quiet similar.
3) Basicity differences:
Basic strength of the hydroxides decreases with increases in the atomic number. La(OH)3 is most basic while Lu(OH)3 is least basic.