The correct order of spin-only magnetic moment (in $BM$) for $Mn^{2+}$,$Cr^{2+}$,and $Ti^{2+}$ ions is:

The aqueous solution of which of the following ion is colourless?

Which of the following substances will have the highest magnetic moment for its transition metal ion?

Given below are two statements: one is labelled as Assertion $(A)$ and the other is labelled as Reason $(R)$.
Assertion $(A):$ $Cu^{2+}$ in water is more stable than $Cu^{+}$.
Reason $(R):$ Enthalpy of hydration for $Cu^{2+}$ is much less than that of $Cu^{+}$.
In the light of the above statements,choose the correct answer from the options given below:

Because of lanthanoid contraction,which of the following pairs of elements have nearly same atomic radii? (Numbers in the parenthesis are atomic numbers)

In which block does the $106^{th}$ element belong?