Molecular Orbital Theory (Its Important features. LCAOs, types of molecular orbitals (bonding, antibonding), sigma and pi-bonds, molecular orbital electronic configurations of homonuclear diatomic molecules, the concept of bond order, bond length, and bond energy )
Molecular Orbital Theory (Its Important features. LCAOs, types of molecular orbitals (bonding, antibonding), sigma and pi-bonds, molecular orbital electronic configurations of homonuclear diatomic molecules, the concept of bond order, bond length, and bond energy ) MCQ Questions
13.
Sigma (Ο) molecular orbitals are:
A.
Asymmetrical around the bond axis
B.
Symmetrical around the bond axis
C.
Always have nodes at the nucleus
ANSWER :
B. Symmetrical around the bond axis
14.
Pi (Ο) molecular orbitals are:
A.
Higher in energy than Ο* always
B.
Symmetrical around the bond axis
C.
Not symmetrical around the bond axis (have positive lobe above and negative lobe below)
D.
Identical to sigma orbitals
ANSWER :
C. Not symmetrical around the bond axis (have positive lobe above and negative lobe below)
15.
Linear combination of 1s atomic orbitals of two atoms gives:
A.
Only one molecular orbital
B.
Ξ΄1s molecular orbital
C.
Ο1s and Ο*1s molecular orbitals
D.
Ο1s and Ο*1s molecular orbitals
ANSWER :
C. Ο1s and Ο*1s molecular orbitals
16.
When two 2pz atomic orbitals combine along the z-axis (bond axis), the molecular orbitals formed are:
ANSWER :
C. Ο2pz and Ο*2pz
17.
When 2px atomic orbitals combine (with bond axis being z), the molecular orbitals formed are:
ANSWER :
B. Ο2px and Ο*2px
18.
Which molecular orbitals are degenerate (equal in energy)?
A.
Ο2px and Ο2py (and similarly Ο*2px and Ο*2py)
ANSWER :
A. Ο2px and Ο2py (and similarly Ο*2px and Ο*2py)
