Chapter 2: 2.3 Relationship Between pH and pKa Flashcards

1
Q

Define:

pH

A

A measurement made for how acidic a solution is

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Define:

pKa

A

A measurement made for how acidic a hydrogen atom on a molecule is

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

If asked which side of an equilibrium is favoured, which side do you pick?

A

Pick the side with the more stable conjugate base

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

The pH of a solution will have an effect on the…

A

Predominant structure of an acid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

State:

The ratio of protonated acid (HA) to its conjugate base (A-) when:
1. pH = pKa
2. pH > pKa
3. pH < pKa

A
  1. Concentration of HA equals A-
  2. More basic pH, increases quantity of A-
  3. More acidic pH, increases quantity of HA
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Amino acids are the building blocks of…

A

Proteins and enzymes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

True or False:

Amino acids can be used to explore the relationship of pH to pKa

A

True

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

How are amino acids:
1. Similar?
2. Different?

A
  1. All feature an amine and a carboxylic acid functionality
  2. Differ in the structure of their side chain (a key feature of their reactivity)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

We can predict the predominant structure of an amino acid in various pH solutions. Give the pH of the following:
1. Acidic solution
2. Neutral solution
3. Basic solution

A
  1. pH = 1-3
  2. pH = 6-8
  3. pH = 11-13
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

If pH is below the pKa, the functional group of an amino acid is…

A

Protonated

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

If the pH is above the pKa, the functional group of an amino acid is…

A

Deprotonated

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Important pKas to know:

Sulfuric acid

A

-9

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Important pKas to know:

Hydronium

A

-2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Important pKas to know:

Carboxylic acid

A

4

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Important pKas to know:

Phenols

A

10

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Important pKas to know:

Ammonium

A

10

17
Q

Important pKas to know:

Water

A

16

18
Q

Important pKas to know:

Alcohols

A

16

19
Q

Important pKas to know:

Alkynes

A

25

20
Q

Important pKas to know:

Amines

A

40

21
Q

Important pKas to know:

Alkenes

A

45

22
Q

Important pKas to know:

Alkanes

A

50

23
Q

Important pKas to know:

Aldehydes

A

17

24
Q

Important pKas to know:

Ketones

A

20

25
Q

Important pKas to know:

Esters

A

25