Question

The number of completed transitional series in the periodic table is / are:

• A. $2$
• B. $3$
• C. $4$
• D. $1$

Answer 1

Answer: (B)

$3$

Transition series of elements are d block elements.There are $4$ transition series are present they are:
$3d$-series-scandium to zinc
$4d$-series-yttrium to argentinum
$5d$-series-lanthanum to hydragyrum(mercury)
$6d$-series-actinium and these series is incomplete.