Question

Which one of the following is '$d$'-block element?

• A. $Gd$
• B. $Hs$
• C. $Es$
• D. $Cs$

Answer 1

Answer: (B)

$Hs$

Hassium, $Hs(Z=108)$ is '$d$'-block element. It belongs to the seventh period and VIII B group (group 8).

It has electronic configuration $\left[Rn\right]5f^{14}6d^{6}7s^2$

$Gd$ is lanthanoid ($f$ block element).
$Es$ is actinoid ($f$ block element).
$Cs$ is an alkali metal ($s$ block element).

Hence, option $B$ is correct.