91影视

To find the valence electrons of the given ions, we can look at their position in the periodic table. - \(\operatorname{In}^{+}\) (Indium) has a group number of 13 (3 valence electrons) and is losing 1 electron to form the ion, giving it \((3-1)=2\) valence electrons. - \(\mathrm{I}^{-}\) (Iodine) has a group number of 17 (7 valence electrons) and is gaining 1 electron to form the ion, giving it \((7+1)=8\) valence electrons. - \(\mathrm{Ca}^{2+}\) (Calcium) has a group number of 2 (2 valence electrons) and is losing 2 electrons to form the ion, giving it \((2-2)=0\) valence electrons. - \(\mathrm{Sn}^{2+}\) (Tin) has a group number of 14 (4 valence electrons) and is losing 2 electrons to form the ion, giving it \((4-2)=2\) valence electrons.

Remember that Lewis symbols represent valence electrons using dots around the chemical symbol. - \(\operatorname{In}^{+}\): 2 valence electrons ``` In鈦� 路 路 ``` - \(\mathrm{I}^{-}\): 8 valence electrons ``` I鈦� 路路: :路路 ``` - \(\mathrm{Ca}^{2+}\): 0 valence electrons ``` Ca虏鈦� ``` - \(\mathrm{Sn}^{2+}\): 2 valence electrons ``` Sn虏鈦� 路 路 ```

An ion with a complete valence-shell octet will have 8 valence electrons. In this case, only \(\mathrm{I}^{-}\) has 8 valence electrons.

The Lewis symbols for the ions are: - \(\operatorname{In}^{+}\): ``` In鈦� 路 路 ``` - \(\mathrm{I}^{-}\): ``` I鈦� 路路: :路路 ``` - \(\mathrm{Ca}^{2+}\): ``` Ca虏鈦� ``` - \(\mathrm{Sn}^{2+}\): ``` Sn虏鈦� 路 路 ``` Only the \(\mathrm{I}^{-}\) ion has a complete valence-shell octet.