Chapter 23, Problem 27QAP

Interpretation Introduction

(a)

Interpretation:

The structure of zwitterionic form of cysteine needs to be drawn.

Concept introduction:

Amino acids are organic compounds containing amino as well as acidic groups. The general molecular formula of an amino acid is as follows:

${\text{H}}_{\text{2}}\text{N-CH}\left(R\right)-\text{COOH}$

Here, R refers to different group for different amino acids. If there is more than one amino group present in an amino acid, they are considered as basic amino acids and if there is more than one carboxylic group then, they are considered as acidic amino acids.

A zwitterion contains both positively and negativity charged groups in one molecule.

Interpretation Introduction

(b)

Interpretation:

The structure of cation formed from cysteine after the reaction with acid needs to be drawn.

Concept introduction:

Amino acids are organic compounds containing amino as well as acidic groups. The general molecular formula of an amino acid is as follows:

${\text{H}}_{\text{2}}\text{N-CH}\left(R\right)-\text{COOH}$

Here, R refers to different group for different amino acids. If there is more than one amino group present in an amino acid, they are considered as basic amino acids and if there is more than one carboxylic group then they are considered as acidic amino acids.

Interpretation Introduction

(c)

Interpretation:

The structure of anion formed from cysteine after the reaction with base needs to be drawn.

Concept introduction:

Amino acids are organic compounds containing amino as well as acidic groups. The general molecular formula of an amino acid is as follows:

${\text{H}}_{\text{2}}\text{N-CH}\left(R\right)-\text{COOH}$

Here, R refers to different group for different amino acids. If there is more than one amino group present in an amino acid, they are considered as basic amino acids and if there is more than one carboxylic group then they are considered as acidic amino acids.