An element having the electronic configuration $[Ar]3d^24s^2$ belongs to

Why is the first ionisation enthalpy of $Cr$ lower than that of $Zn$?

The number of electrons in the outermost shell of the $3d-$ transition elements generally remains:

Cupric compounds are more stable than their cuprous counterparts in the solid state. This is because

Which of the following has a colored aqueous solution?

Technetium,the element below manganese in the Periodic Table,would be expected to have high values for its:
$(I)$ melting point
$(II)$ boiling point
$(III)$ density