Topic 12: Molecular Orbital Theory, Video A: Visualizing Sigma Bonds From S Orbitals

Question 1

What does it mean when waves are in phase?

Answer 1

It means the waves have the same frequency and amplitude and have the same peaks and valleys. This makes a new larger wave (constructuve interference).

Question 2

What does out of phase mean?

Answer 2

It means you subtract waves. (destructive interference, lower amplitude.)

Question 3

What is the difference between VBT and MO theory?

Answer 3

VBT allow for only paired electrons (not all electrons are paired) No prediction for paramagnetism in molecules.

Question 4

What are the 2 planes of symetry?

Answer 4

xy, xz

Question 5

What happens when atoms are out of phase?

Answer 5

Nuclear repulsions are maximized and no bond is formed. (called antibonding).

Question 6

What is the third difference with VBT?

Answer 6

VBT does not allow for spectroscopy (can only analyze molecules in their ground state.

Question 7

What is the first difference between VBT and MOT.

Answer 7

MO and VBT electron density are different.

Question 8

What are the 3 planes of symetry?

Answer 8

xy, xz, and yz

Question 9

What is the axis of rotation?

Answer 9

Where you rotate the atom and the shape does not change.

Question 10

What happens when atoms are in phase?

Answer 10

Nuclear repulsions are minimized and a bond is formed.