Molecular Structure And Bonding Mock Tests

According to molecular orbital theory, which of the following species has the highest bond order? (Atomic numbers: N = 7, O = 8)

In the molecular orbital diagram of carbon monoxide (CO), a heteronuclear diatomic molecule, the highest occupied molecular orbital (HOMO) has which character? (Consider the relative orbital energies: oxygen is more electronegative than carbon, so oxygen atomic orbitals are lower in energy. The MO diagram shows that the 3σ orbital, derived primarily from carbon 2p_z and some 2s mixing, is the HOMO. Note that CO has 10 valence electrons: 4 from C and 6 from O.)

According to molecular orbital theory, why is O₂ paramagnetic?

The Cramer rule is used to solve the Hückel secular determinants. For butadiene (CH₂=CH-CH=CH₂), the Hückel secular determinant gives four π molecular orbital energies. The total π-electron binding energy (in units of β, where β < 0) for the ground state of butadiene (4 π electrons) is:

The Cramer rule is used to solve a system of linear equations arising from the LCAO-MO method. For the Hückel treatment of ethene (C₂H₄), the secular determinant is: |(α - E), β; β, (α - E)| = 0. The two π molecular orbital energies are:

What is the bond order and magnetic property of the superoxide ion O₂⁻ according to Molecular Orbital Theory? (Total electrons = 17)

Which of the following diatomic species has the shortest bond length? (Use molecular orbital theory to determine the bond order for each species. Higher bond order generally correlates with shorter bond length. Consider the effect of the number of electrons in bonding versus antibonding orbitals.)

The HOMO of 1,3-butadiene (in its ground state) has how many nodes between carbon atoms?