Which one of the following statements related to lanthanons is incorrect ?

Options

A. All the lanthanons are much more reactive than aluminium
B. `Ce( + 4)` solutions are widely used as oxidizing agent in volumetric analysis
C. Europium shows +2 oxidation state
D. The basicity decreases as the ionic radius decreases from Pr to Lu

Answer

A

Explanation

(a) Lanthanon’s are less reactive than aluminium due to high IP (Lanthenoid contraction)
(b) `Ce^(+4)` is good oxidising agent and easily converted into `Ce^(+3)`
`Eu(63) = 4f^7 5d^10 6s^2, Eu^(+2) = 4f^7`
(d) In lanthenoids series ‘Ce’ to Lu ionic radius regular decreases and covalent character increase, basic character of hydroxide decrease.