d- and f-Block Elements

Given below are two statements : In the light of the above statements, choose the most appropriate answer from the options given below :

1. Both Statement I and Statement II are false
2. Statement I is true but Statement II is false
3. Both Statement I and Statement II are true
4. Statement I is false but Statement II is true

Answer

(3) Both Statement I and Statement II are true

Solution

Ce (Z = 58): [Xe]4f1 5d1 6s2 ⇒ Ce4+: [Xe] (noble gas configuration) ⇒ Statement I is true.

E (Ce4+/Ce3+) = +1.74 V ⇒ Ce4+ readily gains an electron to give the common +3 state ⇒ strong oxidant ⇒ Statement II is true.

Answer: (3)