How would you account for the irregular variation of ionization enthalpies (first and second) in the first series of the transition elements ?

Assign a reason for each of the following observation : (i) The transition metals are hard and have high melting and boiling points (ii) The ionisation enthalpies (first and second) in the first series of the transition elements are found to vary irregularly

The second series of transition element start with

Why is enthalpy of atomisation is the lowest for Zn in 3d series of transition elements ?

To what extent do the electronic configurations, decide the stability of oxidation states in the first series of the transition elements? Illustrate your answer with examples.

The first ionisation energies of the elements of the transition series.

Account for the fact that the third ionization enthalpies of both Mn and Zn are higher than those of next element

Name the first and second elements of groups 14.

How would you account for the occurrence of sickle-cell anaemia in human population?

How would you account for the following : (i) The metallic radii of the third (5d) series of transition metals are virtually the same as those of the corresponding group members of the seconds (4d) series. (ii) There is a greater range of oxidation states among the actinoids than among the lanthanoids.

The first transition series is called __________transition series.