The coinage metals are

The spin-only magnetic moment value of $M^{3+}$ ion (in gaseous state) from the pairs $Cr^{3+}/Cr^{2+}$,$Mn^{3+}/Mn^{2+}$,$Fe^{3+}/Fe^{2+}$,and $Co^{3+}/Co^{2+}$ that has a negative standard electrode potential,is $B.M.$ (Nearest integer).

The correct order of decreasing second ionisation enthalpy of $Ti(22), V(23), Cr(24)$ and $Mn(25)$ is

Which of the following may be colourless?

Which of the following sequences does not match the property indicated with it?

The pair of ions with paramagnetic nature and same number of electrons is