The chloride of which of the following elements will be coloured?

Which of the following is wrongly matched?

Which of the following sets correctly represents the increase in the paramagnetic property of the ions?

The element with the highest standard reduction potential (in volt) for the process $M^{2+} \rightarrow M$ among the first row of transition elements is:

Fill in the blanks:
$(a)$ The shielding effect of $d$-electrons is ......... effective than $p$-electrons.
$(b)$ $A$ decrease in exchange energy leads to a ......... in stability.
$(c)$ The maximum oxidation state of $Mn$ is ..........
$(d)$ The stability of $Mo(VI)$ and $W(VI)$ is found to be .......... than that of $Cr(VI)$.

The magnetic moments for $Ti^{2+}$,$V^{3+}$,and $Ni^{2+}$ are respectively: