Common oxidation state of f-block elements is III. The other stable oxidation state of `.^63Eu` and `.^65Tb` are respectively

Options

A. II, IV
B. IV, II
C. II, IV
D. V, II

Answer

A

Explanation

Common oxidation state of f-block elements is (+) 3 but Eu and Tb can also show (+)2 and (+) 4 oxidation states respectively because of `4 f^(7)` and `4 f^(9)` electrons in 4f-subshell respectively.
Hence, option (a) is the correct answer.