Molecular Geometry: Videos & Practice Problems

Estimate the bond angles for the C—N—C bonds in a tertiary amine.

Find out the hybridization and bond angles (approximately) of the central atoms in the following molecules. Also, draw their three-dimensional structures including lone pairs of electrons (if any).

a. HCOOH
b. (CH₃CH₂)₃N
c. [CH₃CH₂NH₃]⁺

Predict the molecular geometry and the Lewis structure of HCO ₂^–.

In most of the amines, the nitrogen has an sp³ hybridization with a pyramidal geometry having bond angles close to 109°. In contrast, the nitrogen atom in methanamide has sp² hybridization and trigonal planar geometry with bond angles of 120°, approximately. Explain this unusual behavior.

Indicate the hybridization and predict the approximate bond angles for each of the carbons in acetylene (HC≡CH).

Keeping the resonance in mind, suggest the hybridization and geometry of the central atoms (only carbon and nitrogen) in the given species.

What orbitals are used in the bonding in AlH₃? Also, describe the bond angles in it.

Provide the hybridization of each carbon atom and approximate the bond angles of the given molecule.

CH₃CH₂CH═CH—CH═CHCH₃

Do the indicated sp³ carbons lie in the same plane as the sp² carbons in the following molecules?

Encircle the atoms that will most likely lie on the same plane.

Estimate the bond angles in the following.

a. tert-butyl radical

b. tert-butyl cation

c. tert-butyl anion

There are four collinear atoms in hex-3-yne (CH₃CH₂CCCH₂CH₃). Draw its three-dimensional structure and circle all the atoms that are in a straight line with the triple bond.

Estimate the bond angles for the bonds mentioned below.

a. the H—C—N bond in HC≡N.

b. the C—C—N bond in CH₃CH₂NHCH₃.

Give the hybridization, bond angles, and geometry of central atoms in the following compound.

• Prop-1-ene, CH₂=CHCH₃

Determine the hybridization of the central atoms in the given compound to predict their bond angles and geometry.

• CH₂=N-CH₃

Identify which of the given species have 109.5° bond angles and which have 120° bond angles around their central atom.

a. AlCl₃

b. CCl₄

c. NH₄⁺

d. BH₃

Provide the Lewis structure for HCHO and predict the shape around its central atom.

Identify the orbitals used to form the bonds and determine the bond angles in CH₃S^– ion.

Determine the hybridization and give the bond angles around the highlighted carbon atoms for the species given below:

(i)

(ii)

Determine the hybridization of each carbon atom and the magnitudes of all bond angles for the molecule CH₃CH=CHCH₃.

Consider the following species: CF₄, ⁺CH₃, and BH₃. Identify those with bond angles of:

(i) 120°

(ii) 109.5°

Estimate the value of the C–O–C bond angle in the following ether molecule.

What is the approximate value of the C–N–C bond angle in dimethylammonium ion? 

Identify the orbitals used to form the bonds and the bond angles in H₂CS.

Determine (i) the orbitals used to form the bonds and (ii) the bond angles in O₂.

Estimate the values for (i) the H—C—O bond angle in the ether CH₃CH₂OCH₂CH₃ and (ii) the H—C—N bond angle in the secondary amine (CH₃CH₂)₂NH.

Estimate the values for the C—N—C and the C—N—H bond angles in the secondary amine (CH₃CH₂CH₂)₂NH.

Convert the molecular model of methylamine into a 3D structure that uses dashes and wedges.

For [CH₃NH]^– ion, write the appropriate Lewis structures and show the types of orbitals that overlap to form each of the chemical bonds. Also determine the bond angle around each atom.

For the following compound:
(i) Draw the appropriate Lewis structure.
(ii) Identify the type of orbital used by every carbon to make chemical bonds and estimate the bond angles.

CBr₄

(i) What is the three-dimensional structure of NH₃?

(ii) What is the hybridization of its nitrogen atom?

(iii) Explain why its bond angle is 107°.

Give the appropriate Lewis structures for the CH₂=NH molecule and determine the types of orbitals that overlap to form each of the chemical bonds. Identify the bond angle around each atom except for hydrogen.