Question

Due to lanthanide contraction the 2 and 3 transition elemesnt nearly the same.Explain

Answer 1

The lanthanides include the metals cerium (Ce), praseodymium (Pr), neodymium (Nd), promethium (Pm), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb), and lutetium (Lu).

Answer 2

The Lanthanide Contraction is caused by a poor shielding effect of the 4f electrons. Gd because as atomic number increases, the atomic radius decreases.

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