To determine which element requires the least amount of energy to give up an electron when forming chemical bonds, we need to consider their positions and properties on the periodic table:
1. Barium (Ba):
- Barium is in Group 2 (the alkaline earth metals) and in Period 6 of the periodic table.
- Elements in Group 2 typically have lower ionization energies than elements in Groups 14 (Silicon) and 16 (Sulfur).
- Ionization energy generally decreases as you move down a group.
2. Sulfur (S):
- Sulfur is in Group 16 and Period 3 of the periodic table.
- Elements in Group 16 have higher ionization energies compared to those in Group 2 because they are nonmetals and tend to gain, rather than lose, electrons.
3. Silicon (Si):
- Silicon is in Group 14 and Period 3 of the periodic table.
- While its ionization energy is lower than that of Sulfur, it is still higher than that of the elements in Group 2.
4. Calcium (Ca):
- Calcium is in Group 2 and Period 4 of the periodic table, just like Barium but in an earlier period.
- Calcium has a lower ionization energy compared to Sulfur and Silicon but higher than Barium as ionization energy decreases down the group.
Considering these points, we can conclude that Barium (Ba), being lower in Group 2 than Calcium, has the lowest ionization energy among the elements provided. Thus, Barium requires the least amount of energy to give up an electron when forming chemical bonds.
Therefore, the element that requires the least amount of energy to give up an electron is:
Barium