Variable valency is shown by

In chromyl chloride,the number of $d$-electrons present on chromium is same as in (Given atomic number of $Ti = 22, V = 23, Cr = 24, Mn = 25, Fe = 26$)

What is the numerical value of spin only magnetic moment of copper in $+2$ state?

$A$ transition metal $X$ has a configuration $[Ar]3d^4$ in its $+3$ oxidation state. Its atomic number is

To what extent do the electronic configurations decide the stability of oxidation states in the first series of the transition elements? Illustrate your answer with examples.

The divalent ion of which of the following elements in an aqueous solution has a magnetic moment of $5.92 \ BM$?