Quiz 3 Big Ideas

If a molecule has more bonding electrons, it means _______ and ______ bonds

stronger, shorter

Describe the credibility of resonance forms.

All resonance forms, as long as they follow the octet rule, are valid. None are the correct representation of the molecule, but one is the best.

What is polarity?

The uneven sharing of electrons

What makes atoms electronegative in a molecule?

If they don’t share electrons nicely.

How do you determine steric number?

By drawing a lewis structure and counting the groups of electrons surrounding that atom.

What are the two requirements for a molecule to be polar?

1. polar bonds

2. must be a net polarity (bonds can’t cancel out)

Why do electrons want to stay far away from each other?

Because their charges repel each other, creating the largest bond angle possible.

How do you know the number of MOs in a molecule?

The number of AOs = the number of MOs

In-phase mixing vs Out-of-phase mixing

In-phase -> constructive interference -> wave density adds

Out-of-phase -> destructive interference -> wave density cancels

What are sigma bonds?

Single bonds that are cylindrically symmetrical

What is the order of energy from least to greatest of the types of orbitals? Why?

Bonding < AOs < antibonding

Bonding orbitals have larger wavelengths, making them more stable and lowest in energy

What should you consider when finding MO configuration?

Only valence electrons

What are the 3 types of orbitals?

AOs: orbitals of individual atoms before hybridization (i.e. s, p, d)

HOs: orbitals of individual atoms to prepare for hybridization, dependent on steric number (i.e. sp, sp2, sp3)

MOs: mixture orbitals of each atom in the bond (i.e. sigma, pi)

How do you know the hybridization of terminal atoms?

They will hybridize to match the central atom of they can. If not, they will omit the orbitals they don’t have access to.