The electronic configuration (outermost) of $Mn^{2+}$ ion (atomic number of $Mn = 25$) in its ground state is

What is the name of the element with atomic number $105$?

Match the following elements in List-$I$ with their respective groups in List-$II$.

List-$I$ (Elements)	List-$II$ (Group)
$A$. $Mn, Tc, Re$	$IV$. $7$
$B$. $Zn, Cd, Hg$	$I$. $12$
$C$. $Ti, Zr, Hf$	$II$. $4$
$D$. $Ga, In, Tl$	$V$. $13$

The correct answer is:

$A$ transition metal $M$ among $Sc, Ti, V, Cr, Mn$ and $Fe$ has the highest second ionisation enthalpy. The spin only magnetic moment value of $M^{+}$ ion is $. . . . . . . BM$ (Near integer)
(Given atomic number $Sc: 21, Ti: 22, V: 23, Cr: 24, Mn: 25, Fe: 26$)

General electronic configuration of outermost and penultimate shell is $(n - 1)s^2 (n - 1)p^6 (n - 1)d^x ns^2$. If $n = 4$ and $x = 5$,then the number of protons in the nucleus will be:

The yellow colour of chromate ion and orange colour of dichromate ion is due to