Video Transcript
Given the data of successive
ionization energies in kilojoules per mole in the table shown, which of the
following elements is most likely to be in group three of the periodic table?
The table provides the successive
ionization energies of five unknown elements from the first ionization energy to the
sixth. Successive ionization energies are
values that quantify how much energy is needed to consecutively remove electrons
from one gaseous state element. A specific element’s pattern of
consecutive ionization energies provides insight to the electronic configuration of
its atoms.
Generally, ionization energy
increases as more electrons are removed. Removing electrons from positively
charged ions requires more energy. However, large increases in
ionization energy that are significantly different from the general increase
indicate that electrons are being removed from an energy level closer to the
nucleus. Electrons closer to the nucleus are
more tightly bound by the electrostatic attraction, so more energy is required to
remove them.
Let’s have a look at the patterns
of each of the five unknown elements to uncover their electronic configurations and
determine which could be in group three of the periodic table. Element one has the most
significant increase in ionization energy between the fourth and fifth ionization
energies. This indicates that the first four
electrons removed were likely in the same energy level and were more loosely bound
than the fifth. The fifth electron removed was
likely in an energy level closer to the nucleus than the first four electrons. Therefore, it is likely that
element one has four valence electrons and can be found in group four of the
periodic table, which we might also call group 14, depending if we count the d-block
transition metals.
Element two shows the most
significant increase between the first and second ionization energies. Therefore, it is likely that
element two is in group one of the periodic table. Element three has the most
significant increase between the second and third ionization energies. It is likely that element three is
in group two of the periodic table. Element four has the largest
increase between the third and fourth ionization energies. It is likely that element four is
in group three or 13 of the periodic table. Finally, element five has no
increases that are significantly different from the rest and, thus, could be in
group 16, 17, or 18.
Therefore, the element that is most
likely to be in group three of the periodic table is element four.
