CHM 501

15. For each of the following species write the lowest energy Lewis structure, indicate the formal charge and oxidation number of each atom, show the geometric structure and estimate the bond angles, indicate the σ hybridization about the central atom, and give the point group. a) XeO3, b) XeOF2, c) XeO64–, d) KrF2, e) SeF4.

Answer

a) XeO3

formal charges: O, 0; Xe, 0.

oxidation numbers: O, -2; Xe, +6.

geometric structure: pyramidal, O-Xe-O angles ~108°

Xe hybridization: sp3

point group: C3v

b) XeOF2

formal charges: O, 0; Xe, 0; F, 0.

oxidation numbers: O, -2; Xe, +4; F, -1.

geometric structure: bent-T, O-Xe-F angles ~89°

Xe hybridization: dsp3

point group: C2v

c) XeO64–

formal charges: =O, 0; -O, -1; Xe, 0.

oxidation numbers: O, -2; Xe, +8.

geometric structure: octahedral, all O-Xe-O angles 90°

Xe hybridization: d2sp3

point group: Oh

d) KrF2

formal charges: F, 0; Kr, 0.

oxidation numbers: F, -1; Kr, +2.

geometric structure: linear, F-Kr-F 180°

Kr hybridization: dsp3

point group: D∞h

e) SeF4

formal charges: F, 0; Se, 0.

oxidation numbers: F, -1; Se, +4.

geometric structure: see-saw, F-Se-F angles of ~118° and ~88°

Se hybridization: dsp3

point group: C2v