(i) Electronic configuration: The elements in the same vertical column generally have similar electronic configuration. First transition series shows only two exceptions, i.e., \(\mathrm{Cr}=3 d^5 4 s^1\) and \(\mathrm{Cu}=3 d^{10} 4 s^1\). But second transition series shows more exceptions, i.e., \(\mathrm{Y}=4 d^1 5 s^2, \mathrm{Nb}=4 d^4, 5 s^1, \mathrm{Mo}=4 d^5 5 s^1, \mathrm{Ru}=4 d^7 5 s^1\), \(\mathrm{Rh}=4 d^8 5 s^1, \mathrm{Pd}=4 d^{10} 5 s^0, \mathrm{Ag}=4 d^{10} 5 s^1\). In third transition, there are two exceptions, i.e., \(\mathrm{Pt}=5 d^9 6 s^1\) and \(\mathrm{Au}=5 d^{10} 6 s^1\).
Thus in the same vertical column, in a number of cases, the electronic configuration of the elements of three series are not similar.
(ii) Oxidation states: The elements in the same vertical column generally show similar oxidation states. The number of oxidation states shown by the elements in the middle of each series is maximum and minimum at the extreme ends.
(iii) Ionization enthalpies: The first ionization enthalpies in each series generally increases gradually as we move from left to right though some exceptions are observed in each series. The first ionization enthalpies of some elements in the second \((4 d)\) series are higher while some of them have lower value than the elements of \(3 d\) series in the same vertical column. However, the first ionization enthalpies of third \((5 d)\) series are higher than those of \(3 d\) and \(4 d\) series. This is because of weak shielding of nucleus by \(4 f\)-electrons in the \(5 d\) series.
(iv) Atomic sizes: In general, ions of the same charge or atoms in a given series show progressive decrease in radius with increasing atomic number though the decrease is quite small. But the size of the atoms of the \(4 d\) series is larger then the corresponding elements of the \(3 d\) series whereas size of elements of the \(5 d\) series is nearly same as those of \(4 d\) series because of lanthanoid contraction.