Molecular Representations - Ch. 2

Question 1

What are the requirements for hydrogen bonding?

Answer 1

N, O, or F with a lone pair attached to an H

Question 2

What is the important thing to remember when creating condensed structures?

Answer 2

the final structure must have the appropriate number of bonds for each element

Question 3

Describe an aldehyde

Answer 3

C double bond O and C single bond H

Question 4

Describe Carboxylic Acid

Answer 4

C double bond O, C single bond O single bond H

Question 5

Describe an Ester

Answer 5

C double bond O, C single bond O, single bond R

Question 6

Describe an Alkyne

Answer 6

R single bond C triple bond C single bond R

Question 7

Describe Alkyl Halide

Answer 7

Carbon Chain with halogen at the end

Question 8

Describe Alkane

Answer 8

All carbon carbon single bonds

Question 9

Describe Alkene

Answer 9

Carbon chain with a double bond

Question 10

What is the difference between a Ketone and Aldehyde

Answer 10

Ketone has a double bonded O in the middle and Aldehydes have O on the end

Question 11

What are the keys to identifying functional groups?

Answer 11

1. Locate all heteroatoms and pi bonds
2. Classify each heteroatom as part of one functional group

Question 12

What does it mean when an electron is delocalized?

Answer 12

spread out over more than one atom

Question 13

What are two guidelines to drawing resonance structures?

Answer 13

1. Draw electron pushing arrows from either lone pair electrons or pi bonds
2. Draw arrows toward positive charges and away from negative charges

Question 14

Define functional groups

Answer 14

characteristic group of atoms/bonds that possess a predictable chemical behavior

Question 15

What do wedges indicate in a structure?

Answer 15

Groups coming out of the page

Question 16

What do dashes indicate in a structure?

Answer 16

Group going behind the page

Question 17

What is an acyclic compound?

Answer 17

Has no rings

Question 18

What is a cyclic structure?

Answer 18

One ring

Question 19

What is a bicyclic compound?

Answer 19

Has 2 rings

Question 20

What is significant about resonance structures?

Answer 20

show the positive or negative charges are spread out over more than one location

Question 21

What is the significance of delocalization?

Answer 21

stabilizing factor of molecules and ions

Question 22

How do you know when a lone pair is delocalized?

Answer 22

It is located-in-the-p-orbital

Question 23

List the 4 qualifications from most to least significant within resonance structures.

Answer 23

1. greatest number of filled octets
2. fewer formal charges
3. negative charge on more electronegative element
4. equally good Lewis structures are equivalent and contribute equally