Successive ionisation energies

Successive ionisation energies of an element provide evidence for the existence of quantum shells. 

Table 4.3 Successive ionisation energies In for selected atomic substances kJ mol f. Values in parentheses are only approximate...

When there is a very big jump in the value of successive ionisation energies, an electron is being removed from a lower shell, e.g. if this jump happens from the 4th to the 5th ionisation energy, four electrons have been removed from the outer shell during the first four ionisations, and so the element is in Group 4. 

J Deduce an element s Group from successive ionisation energies. 

The successive ionisation energies of an element X are given below ... 

Successive ionisation energies increase steadily until all the 4s and the 3d electrons have been removed, after which there is a large jump in... 

Formation of cations. The increase between successive ionisation energies is compensated for by a similar increase in hydration energies. Thus cations in different oxidation states are energetically favourable for all transition metals. 

We can continue to remove electrons from an atom until only the nucleus is left. We call this sequence of ionisation energies, successive ionisation energies. 

The successive ionisation energies for the first 11 elements in the Periodic Table are shown in Table 3.2. 

From the second to the ninth electrons removed there is only a gradual change in successive ionisation energies. This suggests that all these eight electrons are in the same shell. 

Figure 3.5 The arrangement of electrons in an atom of sodium can be deduced from the values of successive ionisation energies.

Draw a sketch graph to show the log values of the first four successive ionisation energies of a Group 2 element. 

The ionisation energies needed to remove the first, second, third, fourth, etc., electrons from each atom or ion in a mole of gaseous atoms are called successive ionisation energies. 

Values of successive ionisation energies of atoms provide evidence for their electronic configuration. 

The sketch graph shows the 13 successive ionisation energies of aluminium. 

The successive ionisation energies of element A are shown in the sketch graph. 

When an element forms an ion with more than one negative charge, we must use successive electron affinities (this is rather like the successive ionisation energies we used on page 34). The 1st, 2nd and 3rd electron affinities have symbols AH j, AH y... 

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