Exam 9: Molecular Geometry: Shape Determines Function

Use the 1s orbital of hydrogen to form atomic orbitals for H₂ and draw the molecular orbital energy-level diagram. Label the energy levels with the MO symbols. Which of the following species of hydrogen would you predict to be stable based on your energy-level diagram? Explain. H₂²⁺, H₂⁺, H₂, H₂^-, H₂^2-

Identify the local molecular geometry and hybridization at atoms a and b in Ritalin, shown below, which is a drug used to treat attention deficit hyperactivity disorder. In the line drawing, the hydrogen atoms bonded to carbon are not shown explicitly.

Why does the seesaw molecular geometry (ss) have a lower energy than the trigonal pyramidal molecular geometry (tp) in an AB₄ molecule with a trigonal bipyramidal electron-pair geometry?

Which of the following molecules or ions is not polar?

Which statement about VSEPR theory is not correct?

Which of the following molecules has a central atom that is sp³ hybridized?

Identify the hybridization of atomic orbitals for atoms a, b, and c in the structure below of acetaminophen, which is the active ingredient in the analgesic Tylenol.

Which of the following molecules or ions has a central atom with the same hybridization as PCl₅?

Which of these molecules is chiral?

Boron nitride is being investigated in frontier research directed at producing novel electronic devices. If you used the following energy-level diagram for the molecular orbitals of boron nitride, BN, what would you predict? These molecular orbitals are formed from the 2s and 2p atomic orbitals. I. Boron nitride is diamagnetic. II) Boron nitride has a bond order of 2. III) Boron nitride is paramagnetic. IV) The bond in BN^- is stronger than the bond in BN.

All homonuclear diatomic molecules ________

Which of the following ions is linear?

Benzene (C₆H₆) is a cyclic, nonpolar molecule. By removing one of the hydrogens and replacing it with another atom or group, this substituted benzene becomes polar. Which of the following substituted benzenes is the most polar?

Both diazene (N₂H₂) and hydrazine (N₂H₄) have two nitrogen atoms bonded together. In a valence bond picture of the N-N bonds, ________ hybrid orbitals overlap for diazene and ________ hybrid orbitals overlap for hydrazine.

Draw a structure showing the geometry of the molecule in the following group that is nonpolar: HF; NH₃; BF₃; CHCl₃; CO.

Which statement regarding a pi bond between two carbon atoms is correct?

Which of these molecules is chiral?

Which of these molecules have a dipole moment?

Both cyclohexane (C₆H₁₂) and benzene (C₆H₆) have the carbon atoms forming a six-member ring. In a valence bond picture of the C-C bonds, ________ hybrid orbitals would overlap for cyclohexane, and ________ hybrid orbitals would overlap for benzene.

Identify the hybridization of atomic orbitals for atoms N1, N2, C1, C2, and C3 in caffeine, which is shown below. Explain why you think this molecule is planar or nonplanar.