Cr and Cu show high second ionization enthalpies due to the removal of electrons from d orbitals, resulting in d⁵ and d¹⁰ configurations in M²⁺ ions, influencing their stability.

Fe²⁺ has a d⁶ configuration, while Mn²⁺ has a 3d⁵ configuration. The absence of exchange energy loss in the d⁶ configuration of Fe²⁺ results in lower ionization enthalpy compared to Mn²⁺, indicating that the third ionization enthalpy of Fe is ...

Mn⁺ has a 3d⁵4s¹ configuration, while Cr⁺ has a d⁵ configuration. The absence of loss of exchange energy in the d⁶ configuration of Mn⁺ leads to lower ionization enthalpy compared to Cr⁺, showcasing the influence of exchange energy on stability ...

The variation in ionization enthalpy for dⁿ configuration is influenced by the attraction of electrons towards the nucleus, repulsion between electrons, and exchange energy. Exchange energy, proportional to the number of possible pairs of parallel spins, increases stability by following ...

The breaks in the trend of increasing second and third ionization enthalpy occur for Mn²⁺ and Fe³⁺ in the 3d series, where these ions have d⁵ configuration. Similar breaks occur at corresponding elements in later transition series, and these anomalies ...

The addition of electrons to the 3d orbitals in the 3d series enhances the shielding effect of 3d electrons, effectively shielding 4s electrons from the increasing nuclear charge. As a result, the atomic radii decrease less rapidly, leading to only ...

The irregular trend in the first ionization enthalpy is attributed to the alteration of relative energies between 4s and 3d orbitals upon the removal of one electron, affecting the shielding of 4s electrons by the increasing nuclear charge along the ...

The variation in ionization enthalpy along a series of transition elements is less pronounced than in a period of non-transition elements. While the first ionization enthalpy generally increases, the increase in the second and third ionization enthalpies is significantly higher ...

The lanthanoid contraction results in a decrease in metallic radius and an increase in atomic mass, contributing to a general increase in the density of elements in the transition series from titanium (Z = 22) to copper (Z = 29).

The lanthanoid contraction is caused by imperfect shielding of one 4f electron by another, similar to the shielding observed in an ordinary transition series. However, the shielding effectiveness of 4f electrons is less than that of d electrons, leading to ...