Chapter 15, Problem 15.67P

Interpretation Introduction

(a)

Interpretation:

The chiral center in the lactic acid needs to be located.

Concept introduction:

A molecule is said to be chiral if it is asymmetric in nature. The chiral carbon is defined as the carbon atom attached to 4 different groups. The non-superimposable mirror images of the chiral molecule are known as its enantiomer. Molecules with planes of symmetry do not have chirality. The plane bisecting an object into two identical halves is known as the plane of symmetry. A molecule having a plane of symmetry in any conformation is always identical to its mirror image and such molecules are achiral in nature.

Interpretation Introduction

(b)

Interpretation:

The enantiomers of lactic acid needs to be drawn.

Concept introduction:

The enantiomer is a non-superimposable mirror image of the molecule having a chiral center. A molecule is said to be chiral if it is asymmetric in nature. The chiral carbon is defined as the carbon atom attached to 4 different groups.

Interpretation Introduction

(c)

Interpretation:

The Fischer projections for enantiomers of Lactic acid needs to be drawn.

Concept introduction:

For a molecule with a chiral center, the Fischer projection formula is written to describe the stereo arrangement of atoms in two dimensions. For large molecules with more than 1 stereocenters are also represent their stereochemistry using the Fischer Projection. The carbon chain of the molecule containing the chiral carbon center is represented as a vertical line with chiral carbon at the center. Two other groups are then horizontally arranged around the chiral carbon atom.