人能预测离子的电荷通过检查the atom’s location in the periodic table (Figure 1). Atoms of many main group metals and non-metals tend to lose or gain enough electrons to obtain the same number of electrons as an atom of the noble gasses.

For example, atoms in group 1 and 2 tend to lose electrons to achieve the same number of electrons as the preceding noble gas atom. In contrast, atoms in group 14-17 tend to gain additional electrons to acquire the same electron configuration as the next noble gas in the period.

Figure 1:Ions in theperiodic tableand their charges