Question

What is the oxidation state exhibited by actinium?

(a) +4

(b) +1

(c) +2

(d) +3

The question was asked by my school principal while I was bunking the class.

I'm obligated to ask this question of Electronic Configurations of the D-Block Elements topic in section D and F-Block Elements of Chemistry – Class 12

Answer 1

Correct option is (d) +3

The explanation: Actinium is the first member of the actinoid series. Its atomic number is 89. The electronic configuration of actinium is [Rn]6d^17s^2. It has only three electrons to lose. Therefore, actinium is generally only found in the +3-oxidation state.