The common oxidation state of scandium $(Sc)$,a transition element,is:

The electronic configuration of silver atom in ground state is

Pairs of elements with the same number of electrons in their respective $4f$ orbital are [Atomic number: $Eu-63, Gd-64, Dy-66, Ho-67, Tm-69, Yb-70, Lu-71, Hf-72$]. Choose the correct answer from the options given below:

Which of the following options represents the increasing order of the paramagnetic property of the ions?

Cuprous ion is colourless,while cupric ion is coloured because

Which element belongs to the $d-$block?