Exercícios Geometria Molecular

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Número total de 
pares de 
elétrons em 
torno do átomo 
central 
Números de 
pares isolados 
Geometria dos 
pares de 
elétrons 
Geometria da 
molécula 
Representação. 
 
 
2 
 
 
 
0 
 
Linear 
 
Linear 
 
 
 
1 
 
Linear 
 
Linear 
 
 
 
 
 
 
 
 
3 
 
 
 
 
 
 
 
 
 
 
 
 
0 
 
 
 
Trigonal Plana 
 
 
 
Trigonal Plana 
 
 
 
 
1 
 
 
 
Trigonal Plana 
 
 
 
Angular 
 
 
 
 
2 
 
 
 
Trigonal Plana 
 
 
 
Linear 
 
 
4 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
0 
 
 
 
Tetraédrica 
 
 
 
Tetraédrica 
 
 
 
 
1 
 
 
 
Tetraédrica 
 
 
 
Piramidal 
 
 
 
 
2 
 
 
 
 
 
 
Tetraédrica 
 
 
 
Angular 
 
 
 
3 
 
 
Tetraédrica 
 
 
Linear 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
5 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
0 
 
 
 
Bipirâmide 
trigonal 
 
 
 
Bipirâmide 
trigonal 
 
 
 
 
1 
 
 
 
Bipirâmide 
trigonal 
 
 
 
Gangorra 
 
 
 
 
2 
 
 
 
Bipirâmide 
trigonal 
 
 
 
Forma T 
 
 
 
 
3 
 
 
 
Bipirâmide 
trigonal 
 
 
 
Linear 
 
 
6 
 
 
 
 
 
 
 
 
 
 
 
 
 
0 
 
 
 
 
Octaedro 
 
 
 
 
Octaedro 
 
1 Octaedro Pirâmide de 
base quadrada 
 
 
 
 
2 
 
 
 
Octaedro 
 
 
Quadrada 
planar 
 
 
 
 
Exercícios Geometria Molecular 
 
1) Pick the correct Lewis dot structure for the following molecules: 
a. Si2 
 
 
 
 
 
 
 
 
b. Br2 
 
 
 
 
 
 
 
 
 
c. As2 
 
 
 
 
 
 
 
 
 
d. Se2 
 
 
 
 
 
 
 
 
 
e. CO 
 
 
 
 
 
 
 
 
 
f. SO2 
 
 
 
 
 
 
 
 
 
g. NO2
+1 
 
 
 
 
 
 
 
 
 
h. PO2
-3 
 
 
 
 
 
 
 
 
 
i. SbCl3 
 
 
 
 
 
 
 
 
 
j. BrF3
+2 
 
 
 
 
 
 
 
 
 
k. BO3
-3 
 
 
 
 
 
 
 
 
 
l. PO3
-3 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2) Draw Lewis dot stuctures for each of the following. Then decide what the is the appropriate 
geometry: 
a. SF2 linear trigonal planar tetrahedral bent trigonal pyramid really bent 
b. SiS2 linear trigonal planar tetrahedral bent trigonal pyramid really bent 
c. SeS3 linear trigonal planar tetrahedral bent trigonal pyramid really bent 
d. PH3 linear trigonal planar tetrahedral bent trigonal pyramid really bent 
e. S3 linear trigonal planar tetrahedral bent trigonal pyramid really bent 
f. SiCl4 linear trigonal planar tetrahedral bent trigonal pyramid really bent 
g. AsO3
-1
 linear trigonal planar tetrahedral bent trigonal pyramid really bent 
h. IO2
+1
 linear trigonal planar tetrahedral bent trigonal pyramid really bent 
i. O3
+2
 linear trigonal planar tetrahedral bent trigonal pyramid really bent 
j. BBr3
-2
 linear trigonal planar tetrahedral bent trigonal pyramid really bent 
k. ClF2
+1
 linear trigonal planar tetrahedral bent trigonal pyramid really bent 
3) Based on the following Lewis dot structures, which molecule exhibits resonance? 
 
 
 
 
 
 
 
 
 
 
( ) ( ) ( ) ( ) ( ) ( ) 
 
4) Based on the Lewis dot structures of the following organic molecules, choose the appropriate 
geometry. 
a. 
trigonal planar bent linear tetrahedral trigonal pyramid really bent 
 
b. 
trigonal planar bent linear tetrahedral trigonal pyramid really bent 
 
c. 
trigonal planar bent linear tetrahedral trigonal pyramid really bent 
 
d. 
trigonal planar bent linear tetrahedral trigonal pyramid really bent 
 
e. 
trigonal planar bent linear tetrahedral trigonal pyramid really bent 
 
f. 
trigonal planar bent linear tetrahedral trigonal pyramid really bent 
 
g. 
trigonal planar bent linear tetrahedral trigonal pyramid really bent 
 
h. 
trigonal planar bent linear tetrahedral trigonal pyramid really bent 
5) Use the molecules below to find the formal charges of the specified atoms. 
 
a. N 
-2 -1 0 +1 +2 
b. S 
-2 -1 0 +1 +2 
c. O 
-2 -1 0 +1 +2 
 
d. F 
-2 -1 0 +1 +2 
e. N 
-2 -1 0 +1 +2 
f. S 
-2 -1 0 +1 +2 
g. O 
-2 -1 0 +1 +2 
 
6) Six Lewis dot structures can be constructed using one O atom, one F atom, and one N atom. 
Calculate the formal charges on the atoms in each and use the results to choose the resonance 
structure that is lowest in energy: 
 
 
7) Choose the number of lone pairs located on the central atom for each of the stated molecular 
geometries: 
a. square planar 0 1 2 3 4 
b. octahedral 0 1 2 3 4 
c. linear2 0 1 2 3 4 
d. trigonal bipyramid 0 1 2 3 4 
e. distorted tetrahedron 0 1 2 3 4 
f. square pyramid 0 1 2 3 4 
g. T-shape 0 1 2 3 4 
 
 
 
8) Choose the correct Lewis dot structure and VSEPR geometry of each molecule: 
 
a) XeF2 
 
 
 
 
 
 
 
 
 
 
 
( ) ( ) ( ) 
 
 
( ) ( ) ( ) 
 
b) BrH3 
 
 
 
 
( ) ( ) ( ) 
 
 
 
 
 
( ) ( ) 
 
 
c) KrBr4 
 
( ) ( ) 
 
 
( ) ( ) 
 
d) SeCl4 
 
( ) ( ) 
 
 
( ) ( ) 
 
e) AsH5 
 
 
( ) ( ) 
 
f) ClH5 
 
 
( ) ( ) 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
9) Draw Lewis dot structures for each of the following. Then choose the correct VSEPR geometry. 
a. XeF4 
trigonal 
bipyramid octahedral 
distorted 
tetrahedron 
T-
shape linear2 
square 
pyramid 
square 
planar 
b. SiH5
-1
 
 
trigonal 
bipyramid octahedral 
distorted 
tetrahedron 
T-
shape linear2 
square 
pyramid 
square 
planar 
c. PH3
-2
 
 
trigonal 
bipyramid octahedral 
distorted 
tetrahedron 
T-
shape linear2 
square 
pyramid 
square 
planar 
d. XeCl5
+1
 
 
trigonal 
bipyramid octahedral 
distorted 
tetrahedron 
T-
shape linear2 
square 
pyramid 
square 
planar 
e. BrH4
+1
 
 
trigonal 
bipyramid octahedral 
distorted 
tetrahedron 
T-
shape linear2 
square 
pyramid 
square 
planar 
f. OH6 
trigonal 
bipyramid octahedral 
distorted 
tetrahedron 
T-
shape linear2 
square 
pyramid 
square 
planar 
g. ClF2
-1
 
 
trigonal 
bipyramid octahedral 
distorted 
tetrahedron 
T-
shape linear2 
square 
pyramid 
square 
planar 
h. SBr4 
trigonal 
bipyramid octahedral 
distorted 
tetrahedron 
T-
shape linear2 
square 
pyramid 
square 
planar 
i. SiBr5
-3
 
 
trigonal 
bipyramid octahedral 
distorted 
tetrahedron 
T-
shape linear2 
square 
pyramid 
square 
planar 
j. SH4
-2
 
 
trigonal 
bipyramid octahedral 
distorted 
tetrahedron 
T-
shape linear2 
square 
pyramid 
square 
planar 
k. BrI3 
trigonal 
bipyramid octahedral 
distorted 
tetrahedron 
T-
shape linear2 
square 
pyramid 
square 
planar 
 
 
 
 
10) Choose the number of lone pairs located on the central atom for each of the stated molecular 
geometries: 
a. trigonal pyramid 0 1 2 3 4 
b. linear 0 1 2 3 4 
c. tetrahedral 0 1 2 3 4 
d. really bent 0 1 2 3 4 
e. trigonal planar 0 1 2 3 4 
f. bent 0 1 2 3 4 
 
11) In VSEPR theory, which of the following is a true statement? 
 
Single bonds repel 
more than double 
bonds 
 
Double bonds repel 
more than single 
bonds 
 
Lone pairs repel 
more than bond 
pairs 
 
Bond pairs repel 
more than lone 
pairs 
 
Bond pairs and 
lone pairs repel 
the same 
 
12) Order the bond-types in order of their relative strengths from weakest to strongest. 
 
single < double 
< triple 
 
single < triple < 
double 
 
double < triple 
< single 
 
double < single 
< triple 
 
triple < single < 
double 
 
triple < double 
< single 
 
13) As bexigas de forma ovóide, apresentadas na figura abaixo, representam nuvens eletrônicas 
associadas a ligações simples, duplas ou triplas entre átomos. Levando-se em consideração os 
compostos BeH2, H2O, BF3, CH4, NaCl, BaSO4, SOF4, ICl2
-, BrF3,SF4. 
 
a) Associe, quando possível, os compostos às figuras representadas pelas bexigas. 
b) Faça a geometria molecular dos compostas que não foram representadas pelas bexigas. 
c) Entre as espécies CH4 e H20, qual apresenta menor ângulode ligação? Explique.