Chapter 7 - Alkyl Halides

Question 1

A primary carbon has how many R groups?

Answer 1

One R group

Question 2

A secondary carbon has how many R groups?

Answer 2

Two R groups

Question 3

A tertiary carbon has how many R groups?

Answer 3

Three R groups

Question 4

What kinds of interactions do alkyl halides exhibit?

Answer 4

Diple-dipole and Van der Waals

Question 5

As basicity increases, leaving group ability (increases / decreases)?

Answer 5

As basicity increases, leaving group ability decreases. Basicity and leaving group ability have an inverse relationship.

Question 6

Basicity (increases / decreases) as you go left -> to -> right across the periodic table

Answer 6

Basicity decreases moving left -> to -> right

Question 7

Basicity (increases / decreases) as you go down a column in the periodic table

Answer 7

Basicity decreases moving down a column

Question 8

Iodine is the least basic (organic) element on the periodic table, making it the (best / worst) leaving group

Answer 8

Iodine is the best leaving group on the periodic table

Question 9

What is the difference between a nucleophile and a base?

Answer 9

A base attacks a proton. A nucleophile attacks electron-deficient atoms (usually carbon).

Question 10

Does steric hindrance decrease nucleophilicity or basicity?

Answer 10

Steric hindrance influences nucleophilicity. A base is unaffected by the sterics of a molecule.

Question 11

What substitution mechanism (Sn1 or Sn2) do tertiary carbons undergo?

Answer 11

Tertiary carbons undergo the Sn1 mechanism

Question 12

What substitution mechanism (Sn1 or Sn2) do primary carbons undergo?

Answer 12

Primary carbons undergo the Sn2 mechanism

Question 13

Polar protic solvents form ion-dipole interactions with (cations / anions)

Answer 13

Polar protic solvents form ion-dipole interactions with cations

Question 14

Polar protic solvents form hydrogen bonds with (cations / anions)

Answer 14

Polar protic solvents form hydrogen bonds with anions

Question 15

Sn1 Reactions undergo two separate steps. What does the first step accomplish?

Answer 15

The first step creates a cation for the nucleophile to attack.

Question 16

What three factors affect Sn1 reactions?

Answer 16

1. Structure of the Starting Material
2. Solvent
3. Leaving Group

Question 17

Inductive Effect

Answer 17

The methyl groups on the carbocation are slightly electron donating, which stabilizes the positively charged carbocation.

Question 18

What kind of solvents do Sn1 reactions use? Why do they use these solvents?

Answer 18

Sn1 reactions use polar protic solvents. These solvents are used because they allow the reaction to proceed faster.

Question 19

Which of the following reactions creates a racemic mixture: Sn1 or Sn2?

Answer 19

Sn1 reactions create a racemic mixture

Question 20

How many steps are in an Sn2 reaction? How many components are in it’s rate equation?

Answer 20

There is one step in an Sn2 reaction. It has two components to it’s rate equation: the nucleophile/base and the electrophile/leaving group.