In Class Problems - 10/12/00

1.) Draw the Lewis electron-dot structures for the following species, indicating formal charges and resonance structures where applicable. Are all the resonance structures equal? If not, are any really good or really bad?

a.) HNC (central N atom)

b.) SCN^- (thiocyanate ion)

c.) H₂CNN (the first N atom is bonded to the carbon and the second N)

d.) BrO₄^-

e.) PCl₆^-

f.) XeF₃⁺

g.) AsH₃

h.) HOCl

i.) PO₂Cl₂^-

j.) CH₃NCO

k.) H₃NBF₃

l.) PF₅

m.) SF₄

n.) XeO₂F₂

o.) NO₂

p.) XeF⁺

q.) XeF₂

r.) OPCl

s.) O₂PCl

2.) Use VSEPR theory to determine the electron geometry and the atomic geometry of the species in #1. Draw the molecule. Do only those listed below. Indicate if the species is polar or non-polar.

Species: a, b, d - i, l - n, p - q (from above)

3.) Two possible Lewis structures for sulfine (H₂CSO) are