Answer: The correct relationship of these elements regarding their ionization energy is Strontium < Calcium < Beryllium.
Explanation:
The amount of energy required to remove the most loosely bound electron in an atom is called ionization energy.
Larger is the size of an atom, more easily it can lose an electron. Since the size of atoms increases on moving down in a periodic table so ionization energy decreases down the group.
For example, beryllium, calcium, and strontium are elements of group 2. Strontium is the largest in size and beryllium is the smallest in size.
Hence, the ionization energy of group 2 elements in the increasing order is as follows.
Strontium < Calcium < Beryllium
Thus, we can conclude that the correct relationship of these elements regarding their ionization energy is Strontium < Calcium < Beryllium.
