Bonding and Molecular Geometry

Question 1

Single covalent bond

Answer 1

One sigma (σ) bond

Question 2

Double bonds

Answer 2

One sigma (σ) and one pi (π) bond

Question 3

Triple bonds

Answer 3

One sigma (σ) and two pi (π) bonds

Question 4

ranking covalent bond length and strength

Answer 4

Strongest to weakest: triple bonds, double bonds, single bonds
Shortest to longest: triple bonds, double bonds, single bonds

Question 5

Number of sigma bonds in single bonds

Answer 5

1

Question 6

Number of sigma bonds in double bonds

Answer 6

1

Question 7

Number of sigma bonds in triple bonds

Answer 7

1

Question 8

Number of pi bonds in single bonds

Answer 8

0

Question 9

Number of pi bonds in double bonds

Answer 9

1

Question 10

Number of pi bonds in triple bonds

Answer 10

2

Question 11

Sigma-bonding orbitals in single bonds

Answer 11

Sp³

Question 12

Sigma-bonding orbitals in double bonds

Answer 12

Sp²

Question 13

Sigma-bonding orbitals in triple bonds

Answer 13

Sp

Question 14

Number of sigma-bonding orbitals in single bonds

Answer 14

2

Question 15

Number of sigma-bonding orbitals in double bonds

Answer 15

2

Question 16

Number of sigma-bonding orbitals in triple bonds

Answer 16

2

Question 17

Pi-bonding orbitals in double bonds

Answer 17

2p

Question 18

Pi bonding orbitals in triple bonds

Answer 18

2p

Question 19

Number of pi-bonding orbitals in double bonds

Answer 19

2

Question 20

Number of pi-bonding orbitals in triple bonds

Answer 20

4

Question 21

What is the greatest resonance contributor?

Answer 21

The most stable one:
* most stable resonance structure will have a full octet on every atom
* most stable resonance structure will have the smallest possible number of charges
* most stable resonance structure will have negative charges on the most electronegative atoms and positive charges on the least electronegative atoms

› C⁺ and H⁺ do not have full octets
› N⁺, O⁺, S⁺ do have full octets

Question 22

When drawing the chair conformations, dashed lines point ________ and wedged lines point _______

Answer 22

Down
Up

Question 23

The most stable chair conformation places the molecules highest priority substitute to in the __________ position

Answer 23

Equatorial

Question 24

Eclipsed conformation

Answer 24

Represents the directly overlapping arrangement of atoms or functional groups when looking down the C-C bond. This conformation minimizes the distance between electron densities and thus, the molecule experiences more steric repulsion, leading to decreased stability
This conformation is the least stable when two largest groups are directly overlapping one another

Question 25

Anti staggered conformation

Answer 25

Represented by the same functional group being 180° away from each other
This conformation is more stable than gauche since there is greater distance between the two groups

Question 26

Gauche staggered conformation

Answer 26

Represented by the same functional groups being right next to each other
This conformation is less stable than anti since there is less distance between the two groups

Question 27

Staggered conformation

Answer 27

Represents the non-overlapping arrangement of atoms or functional groups when looking down the C-C bond. This conformation maximizes the distance between electron densities and thus, the molecules experience less steric repulsion, leading to increased stability
The staggered conformation is the most stable when the two largest groups are directly opposite of one another

Question 28

S orbital hybridization s-character and p-character

Answer 28

S-character: 100%
P-character: 0%

Question 29

Sp orbital hybridization s-character and p-character

Answer 29

S-character: 50%
P-character: 50%

Question 30

Sp² orbital hybridization s-character and p-character

Answer 30

S-character: 33%
P-character: 66%

Question 31

Sp³ orbital hybridization s-character and p-character

Answer 31

S-character: 25%
P-character: 75%

Question 32

Resonance of N with lone pairs bonded to 3 things

Answer 32

It may seem like N with a lone pair bonded to 3 things is sp³, but due to being a part of the amide functional group, nitrogen experiences resonance and is actually sp² hybridized

Question 33

stereoisomers:

Answer 33

• molecules with the same molecular formula and connectivity but different spatial arrangement
• two classes: enantiomers and diasteriomers

Question 34

enantiomers:

Answer 34

• non-superimposable, mirror images of each other
• opposite configuration at all chiral centers