Problem 33
Describe the hybridization of phosphorus in \(\mathrm{PF}_{5}\).
Problem 34
How would you distinguish between a sigma bond and a pi bond?
Problem 35
Which of the following pairs of atomic orbitals of adjacent nuclei can overlap to form a sigma bond? Which overlap to form a pi bond? Which cannot overlap (no bond)? Consider the \(x\) axis to be the internuclear axis, that is, the line joining the nuclei of the two atoms. (a) \(1 s\) and \(1 s,\) (b) \(1 s\) and \(2 p_{x},\) (c) \(2 p_{x}\) and (f) \(1 s\) and \(2 s\) s. \(2 p_{y},\) (d) \(3 p_{y}\) and \(3 p_{y}\) (e) \(2 p_{x}\) and \(2 p_{x}\)
Problem 36
What are the hybrid orbitals of the carbon atoms in the following molecules? (a) \(\mathrm{H}_{3} \mathrm{C}-\mathrm{CH}_{3}\) (b) \(\mathrm{H}_{3} \mathrm{C}-\mathrm{CH}=\mathrm{CH}_{2}\) (c) \(\mathrm{CH}_{3}-\mathrm{C}=\mathrm{C}-\mathrm{CH}_{2} \mathrm{OH}\) (d) \(\mathrm{CH}_{3} \mathrm{CH}=\mathrm{O}\) (e) \(\mathrm{CH}_{3} \mathrm{COOH}\)
Problem 37
Specify which hybrid orbitals are used by carbon atoms in the following species: (a) CO (b) \(\mathrm{CO}_{2},(\mathrm{c}) \mathrm{CN}^{-}\)
Problem 38
The allene molecule \(\left(\mathrm{H}_{2} \mathrm{C}=\mathrm{C}=\mathrm{CH}_{2}\right)\) is linear (the three \(\mathrm{C}\) atoms lie on a straight line). What are the hybridization states of the carbon atoms? Draw diagrams to show the formation of sigma bonds and pi bonds in allene.
Problem 39
What is the hybridization of the central \(\mathrm{N}\) atom in the azide ion \(\left(\mathrm{N}_{3}^{-}\right) ?\) (The arrangement of atoms is NNN.)
Problem 41
How many pi bonds and sigma bonds are there in the tetracyanoethylene molecule?
Problem 44
What is molecular orbital theory? How does it differ from valence bond theory?
Problem 45
Define the following terms: bonding molecular orbital, antibonding molecular orbital, pi molecular orbital, sigma molecular orbital.
