91Ó°ÊÓ

Write the Lewis formula for each of the following species. Give resonance forms where appropriate and indicate formal charges. (a) \(\mathrm{CS}_{3}^{2-}\) (b) \(\mathrm{C}_{2} \mathrm{O}_{4}^{2-}\) (c) NCS \(^{-}\)

Write the Lewis formula for each of the following nitrogen oxide molecules. Indicate formal charge and resonance forms. $$ \begin{array}{lll} \text { Formula } & \text { Name } & \text { Form at } 25^{\circ} \mathbf{C}, 1 \text { atm } \\ \hline \mathrm{N}_{2} \mathrm{O} & \text { dinitrogen oxide } & \text { colorless gas } \\ \mathrm{NO} & \text { nitrogen oxide } & \text { colorless gas } \\ \mathrm{N}_{2} \mathrm{O}_{3} & \text { dinitrogen trioxide } & \text { dark blue gas } \\ \mathrm{NO}_{2} & \text { nitrogen dioxide } & \text { brown gas } \\ \mathrm{N}_{2} \mathrm{O}_{4} & \text { dinitrogen tetroxide } & \text { colorless gas } \\ \mathrm{N}_{2} \mathrm{O}_{5} & \text { dinitrogen pentoxide } & \text { white solid } \end{array} $$

Solid sulfur consists of eight-membered rings of sulfur atoms. Write the Lewis formula for a \(\mathrm{S}_{8}\) molecule.

Write Lewis formulas for the resonance forms of the thiosulfate ion, \(\mathrm{S}_{2} \mathrm{O}_{3}^{2-} .\) Indicate formal charges and discuss the bonding in this ion.

White phosphorous has the chemical formula \(\mathrm{P}_{4}(s) .\) A \(\mathrm{P}_{4}\) molecule has 20 valence electrons. Draw a Lewis formula for a white phosphorous molecule in which none of the atoms violates the octet rule and the formal charge on each atom is zero.