Chapter 17.3, Problem 6P

(a)

Interpretation Introduction

Interpretation:

The predominant form of glutamate at $\text{pH }\left(\text{0}\right)$ should be drawn.

Concept Introduction:

Acid-base properties of Amino acids:

 Every amino acid has a carbonyl group and an amino group, and each group can exist in an acidic form or a basic form, depending on $\text{pH}$ of the solution in which the amino acid is dissolved.

The compound exists primarily in the acidic form in solutions that are more acidic than their ${\text{pK}}_{\text{a}}$ values, and primarily in the basic form (without their protons) in solutions that are more basic than their ${\text{pK}}_{\text{a}}$ values.

At $\text{pH=}\text{7}$, $\text{pH}$ of the solution is greater than the ${\text{pK}}_{\text{a}}$ of the carboxyl group then carboxyl group is in the basic form, but less than the ${\text{pK}}_{\text{a}}$ of the protonated amino group then amino acid is in the acidic form.

(b)

Interpretation Introduction

Interpretation:

The predominant form of glutamate at $\text{pH }\left(3\right)$ should be drawn.

Concept Introduction:

Acid-base properties of Amino acids:

Every amino acid has a carbonyl group and an amino group, and each group can exist in an acidic form or a basic form, depending on $\text{pH}$ of the solution in which the amino acid is dissolved.

The compound exists primarily in the acidic form in solutions that are more acidic than their ${\text{pK}}_{\text{a}}$ values, and primarily in the basic form (without their protons) in solutions that are more basic than their ${\text{pK}}_{\text{a}}$ values.

At $\text{pH=}\text{7}$, $\text{pH}$ of the solution is greater than the ${\text{pK}}_{\text{a}}$ of the carboxyl group then carboxyl group is in the basic form, but less than the ${\text{pK}}_{\text{a}}$ of the protonated amino group then amino acid is in the acidic form.

(c)

Interpretation Introduction

Interpretation:

The predominant form of glutamate at $\text{pH }\left(6\right)$ should be drawn.

Concept Introduction:

Acid-base properties of Amino acids:

 Every amino acid has a carbonyl group and an amino group, and each group can exist in an acidic form or a basic form, depending on $\text{pH}$ of the solution in which the amino acid is dissolved.

The compound exists primarily in the acidic form in solutions that are more acidic than their ${\text{pK}}_{\text{a}}$ values, and primarily in the basic form (without their protons) in solutions that are more basic than their ${\text{pK}}_{\text{a}}$ values.

At $\text{pH=}\text{7}$, $\text{pH}$ of the solution is greater than the ${\text{pK}}_{\text{a}}$ of the carboxyl group then carboxyl group is in the basic form, but less than the ${\text{pK}}_{\text{a}}$ of the protonated amino group then amino acid is in the acidic form.

(d)

Interpretation Introduction

Interpretation:

The predominant form of glutamate at $\text{pH }\left(11\right)$ should be drawn.

Concept Introduction:

Acid-base properties of Amino acids:

 Every amino acid has a carbonyl group and an amino group, and each group can exist in an acidic form or a basic form, depending on $\text{pH}$ of the solution in which the amino acid is dissolved.

The compound exists primarily in the acidic form in solutions that are more acidic than their ${\text{pK}}_{\text{a}}$ values, and primarily in the basic form (without their protons) in solutions that are more basic than their ${\text{pK}}_{\text{a}}$ values.

At $\text{pH=}\text{7}$, $\text{pH}$ of the solution is greater than the ${\text{pK}}_{\text{a}}$ of the carboxyl group then carboxyl group is in the basic form, but less than the ${\text{pK}}_{\text{a}}$ of the protonated amino group then amino acid is in the acidic form.