Question

Which of the following group belongs to actinide series ?

• A. Th, Pa, U
• B. Ce Pr, Nd
• C. Ba, La, Hf
• D. Pt, Au, Ag

Answer 1

The correct option is A Th, Pa, U

$Th\left(thorium\right)$, $Pa\left(proactinium\right)$ and $U\left(uranium\right)$ belongs to actinoid series.

$CePr,Nd$ are lanthanoids.

$Ba,La,Hf$ belongs to the sixth period.

$Pt,Au,Ag$ are transition elements.

Hence, option $A$ is correct.