Explanation:
When there will be loss of one or more number of electrons then the atom will acquire a positive charge.
For example, atomic number of calcium is 20 and its electronic distribution is 2, 8, 8, 2.
So, in order to attain stability it loses its 2 valence electrons and this it acquires a +2 charge. Symbol that represents this change is [tex]Ca^{2+}[/tex].
Thus, we can conclude that the symbol representing calcium atoms that have lost two electrons is [tex]Ca^{2+}[/tex].
