Ch.10 - Molecular Shapes & Valence Bond TheorySee all chapters
All Chapters
Ch.1 - Intro to General Chemistry
Ch.2 - Atoms & Elements
Ch.3 - Chemical Reactions
BONUS: Lab Techniques and Procedures
BONUS: Mathematical Operations and Functions
Ch.4 - Chemical Quantities & Aqueous Reactions
Ch.5 - Gases
Ch.6 - Thermochemistry
Ch.7 - Quantum Mechanics
Ch.8 - Periodic Properties of the Elements
Ch.9 - Bonding & Molecular Structure
Ch.10 - Molecular Shapes & Valence Bond Theory
Ch.11 - Liquids, Solids & Intermolecular Forces
Ch.12 - Solutions
Ch.13 - Chemical Kinetics
Ch.14 - Chemical Equilibrium
Ch.15 - Acid and Base Equilibrium
Ch.16 - Aqueous Equilibrium
Ch. 17 - Chemical Thermodynamics
Ch.18 - Electrochemistry
Ch.19 - Nuclear Chemistry
Ch.20 - Organic Chemistry
Ch.22 - Chemistry of the Nonmetals
Ch.23 - Transition Metals and Coordination Compounds

According to the VSEPR Model, bond angles result from surrounding elements and lone pairs around the central element positioning themselves at an optimal distance. 

Idealized Bond Angles

Concept #1: VSEPR Model for Bonding 

The Valence Shell Electron Pair Repulsion (VSEPR) theory gives bond angles based on the number of groups around the central element. 

Concept #2: Ideal Bond Angles

The more lone pairs on the central element then the more compressed the bond angle, and the greater the deviation from an ideal bond angle. 

Concept #3: Lone Pairs & Bond Angles 

Example #1: Determine the bond angles of each of the following compounds. 

CO2

Example #2: Determine the bond angles of each of the following compounds. 

BrF4+

Practice: Determine the bond angle of the following compound. AsCl5

Practice: Determine the bond angle of the following compound: IF3.

Additional Problems
The best predicted shape and bond angle of SbH 3 is 1. trigonal pyramidal; 107°. 2. trigonal pyramidal; 109.5°. 3. tetrahedral; 109.5°. 4. trigonal planar; 120°.
The bond angels in SF5+ are expected to be: a. 90° b. 120° c. 90° and 120° d. 90° and 180° e. 90°, 120° and 180°
The bond angles in NO2Cl (N is the central atom) are 1. 90° 2. < 190.5° 3. 109.5° 4. 120° 5. < 120°
Of the following, which molecule has the largest bond angle? A. SO3 B. SF2 C. HCN D. H2S E. PF3
If PBr3Cl2 is a nonpolar molecule, determine the Cl—P—Br bond angle. a. 120 b. 180 c. 90 d. 109 e. 55  
What is the actual bond angle between oxygen-sulfur bonds on molecules of SO 3? (a) 109.5° (b) < 109.5° (c) > 109.5° (d) 120° (e) <120°
Of the following molecules given below, which has the largest bond angle? a) SO3 b) SF2 c) HCN d) H2S e) PF3
If PBr3Cl2 is a nonpolar molecule, determine the Cl-P-Br bond angle? a. 120 b. 180 c. 90 d. 109 e. 55
What is the value of the smallest bond angle in XeBr 4?   a. 109.5 b. 120 c. 90 d. 180 e. 45
Place the following in order of  increasing X-Se-X bond angle, where X represents the outer atoms in each molecule.   SeO2       SeCl 6       SeF2   A) SeCl6 < SeF2 < SeO2 B) SeF2 < SeO2 < SeCl6 C) SeF2 < SeCl6 < SeO2 D) SeO2 < SeF2 < SeCl6 E) SeCl6 < SeO2 < SeF2
Which of the following molecules would have the smallest angles at the central atom? A. CH4 B. NH3 C. H2O D. CO2 E. PF5
Which molecule has the smallest bond angles? a) CO2 b) H2O c) NH3 d) BF3 e) CCl4
Which one of the following molecules and ions will definitely have at least one 90° bond angle in it? (In each case except water, the central atom is the first one in the formula.)   a) AlCl4 - b) NH3 c) PCl5 d) CO2 e) H2O  
Which of the following has bond angles slightly less than 120 o? NO3- HO2- NO2- CS32- I3+
What set of species is arranged in order of increasing O–N–O bond angle? a) NO2–, NO2, NO2+ b) NO2, NO2–, NO2+ c) NO2+, NO2, NO2– d) NO2, NO2+, NO2–
Which has the largest bond angle? a) angle O–S–O in SO42– b) angle Cl–C–Cl in HCCl 3 c) angle in F–Be–F in BeF2 d) angle in H–O–H in H 2O  
The O–Si–O bond angles in SiO2 (quartz) are closest to  a) 180° b) 120° c) 110° d) 100°
The molecule below has been detected in gas clouds between stars. The predicted C–N–H bond angle is about a) 90° b) 109° c) 120° d) 180°
Draw the Lewis structure of BrF3 and determine the bond angle between an equatorial F atom and an axial F atom = 90º < 90º > 120º = 120 = 109.5º
Which of the following molecules or ions has the   smallest H-N-H bond angle?   NH4+   NH3   NH2−   H2N-NH2   H2N-CH­3
The C—N—O bond angle in nitromethane, CH3NO2, is expected to be approximately 1) 60° 2) 90° 3) 109.5° 4) 120° 5) 180°
In cumulene, what are the C=C=C and H-C-H bond angles, respectively? Enter the C=C=C bond angle followed by the H-C-H bond angle separated by a comma.
Which of the following molecules or ions has the smallest H-N-H bond angle? a) NH4+ b) NH3 c) NH2− d) H2N-NH2 e) H2N-CH3
Draw the Lewis structure for SeF4 and answer the following questions.How many valence electrons are present in this compound?How many bonding electrons are present in this compound?How many lone pair (non-bonding) electrons are present in this compound?Is SeF4 a polar or non-polar compound? What is the geometry of SeF4? What is the shape of SeF4? What are the approximate bond angles made by the atoms in this structure? 
The molecular geometry of NO2- is, Use VSEPR to justify your answer.A) bent, bond angle - 109°B) trigonal planarC) linearD) bent, bond angle - 120°
What is the value of the bond angles in CCl 4?
What is the value of the smallest bond angle in ClF 4-?
What is the value of the bond angles in COH 2?
What is the VSEPR geometry for CIO3-? _________________What is the molecular geometry = shape of CIO3-? ___________________Is CIO3- a polar or non-polar ion? ______________What is the approximate O-Cl-O bond angle in CIO3-? ______________
What is the value of the bond angle in ICl 2-?
NO3- :Molecular geometry?Ideal bond angle?Are polar bonds present?Is there an overall dipole?Octect rule violator and how?
What are the expected bond angles in ICl4+?a. 90°b. 109.5°c. 120°d. 180 °
What is the value of the bond angles in CH4, IF 4-, AlCl3, and I3?
What is the value of the bond angles in SiCl 4?
What is the value of the smallest bond angle in XeF 4?
a) Draw the Lewis Structure for CH3Cl. The central atom is ______. The geometry around the central atom is ______. The bond angle, Cl-C-H, is _______ (geometry).    b) Draw the Lewis Structure for CH2O. The geometry around the central angle is ______. The bond angle, H-C-O, is _______.    c) Draw the Lewis Structure for CH3CN. The geometry around the Carbons to which the Hydrogens are attached is _______. The geometry around the other Carbon is _______. This compound has ____ sigma bonds and _____ pi bonds.
What is the value of the bond angles in BCl 3?
What is the value of the bond angle in I 3-?
The molecular geometries for H2O and SO2 are bent. The H-O-H bond angle in H2O is about 109°, whereas the bond angle for O-S-O is about 120°. Explain using lewis diagrams why the molecules have the same molecular geometry but different bond angles.
Predict the ideal bond angle(s) around each central atom in this molecule. 
1. Draw the Lewis structure of the azide anion N  3-. Give its geometry. Is N3- polar (in the sense of having a non-zero electric dipole moment)?  2. Draw the Lewis structure of nitryl fluoride NO 2F (N is at the center). Give its geometry, including a discussion of the angles. Is NO2F polar?   3. Rationalize the following bond angles: NH 3 106.6°; NF3 102.2°; NCl3 106.8°.
Predict the molecular geometry and bond angle of ClNO. Draw the Lewis structure for the molecule.
A molecule with a seesaw molecular geometry has a bond angle of A) <120° for equatorial bonds and <90 degree for axial bonds B) 180° C) <90° D) 120° for equatorial bonds and 90° for axial bonds E) 120°
Compare the bond angle in H2O to OF2. Which angle is larger? Why?
Determine the Electron geometry, molecular geometry, idealized bond angles for each molecule.PF3, SBr2, CHCl3, CS2
What are the expected bond angles in ICl 4 + ? Check all that apply. a) 90° b) 109.5° c) 120° d) 180°
In cumulene (C4H4) , what are the C=C=C and H-C-H bond angles, respectively? 
PI3Cl2 is a nonpolar molecule. Based on this information, determine the I-P-I bond angle, the Cl-P-Cl bond angle, and the I-P-Cl bond angle.Enter the number of degrees of the I-P-I , Cl-P-Cl, and I-P-Cl bond angles, separated by commas (e.g., 30,45,90)
Label the bond angles in the structures given below based on VSEPR.
Predict the ideal bond angle(s) around each central atom in this molecule.
Predict the ideal bond angle(s) around each central atom in this molecule.
The bond angle in NH3 is (smaller, larger) than the bond angle in CH4 because 1. smaller; nitrogen is smaller than carbon. 2. larger; the bond angles in trigonal planar molecules are larger than those in tetrahedral molecules. 3. smaller; the hybridization of nitrogen results in smaller bond angles than the hybridization of carbon. 4. smaller; the bond angles in trigonal planar molecules are smaller than those in tetrahedral molecules. 5. smaller; the unshared pair of electrons on nitrogen is more repulsive to the bonded electron pairs. 6. larger; the hybridization of nitrogen results in larger bond angles than the hybridization of carbon. 7. larger; nitrogen is larger than carbon.
a. What is the molecular geometry of BrI 5? b. Ignoring lone-pair effects, what is the smallest bond angle in BrI 5? (Express your answer as an integer).
Select the correct value for the indicated bond angle in each of the following compounds:
Determine the bond angle fora. N2O (oxygen is terminal)b. SO2c).H2Sd).PF3
Ignoring lone-pair effects, what is the smallest bond angle in ICl 5?
Compare the shapes and bond angles of these oxynitrogen ions. NO43- NO2- NO2+ NO3-
Predict the approximate bond angles in the following molecule. a. C C-C angle b. H-C-H angle
Select the correct value for the indicated bond angle in each of the following compounds:
Based on the bond angles in CH4, NH3, and H2O. rank the magnitude of these repulsions. Rank from strongest to weakest repulsion. To rank items as equivalent, overlap them.
What are the expected bond angles of ICl 4+? Choose all that apply:a. 90 degreesb. 109.5 degreesc. 120 degreesd. 180 degrees