Identify the correct statements from the following :
I `Eu^(2+)` acts as strong of `Pr^(3+) , Dy^(3+) ` and `Sm^(3+) ` follow the order `Sm^(3+) gt Pr^(3+) gt Dy^(3+)`
II `E^(2+)` acts strong reducing reagent.
III Pu exhibits + 7 oxidation state.

Options

A. I, II only
B. I, III only
C. I, II , III
D. II, III only

Answer

D

Explanation

(i) The ionic radius of lanthanoids follow the following relations
Ionic radius `prop (1)/("atomic number ")`
Atomic number (Z) for Pr = 59
Atomic number (Z) for Dy= 66
and has ionic radil for positive ions as given below
(ii) element Eu (z=63) exist in (+) 2 and (+) 3 oxidation state
`:. (+)` 3 oxidation state is the most common oxidation state for lanthanoids
Thus +2 oxidation state oxides to + 3 esily and `Eu^(2+)` can act as strong reducing agent
(iii) the electronic (II) is correct `(Pu ) (Z=94) =5f^(6) 6d^(0) 7s^(2)`
Therefore it can use maximum of 6+2 =8
electron
Thus can show + 7 oxidation state.
Thus statement (HI ) is also correct Hence option (d ) is the correct answer .