Which one of the following statements is false ?

Options

A. R and S configurations correspond to the enantiomers of an optically active compound
B. The process of converting an optically active compound into a racemate is called racemization
C. A molecule containing a plane of symmetry can be optically active
D. Optical isomers that are not enantiomers are called diastereroisomers

Answer

To determine which statement is false among the given options, we will analyze each statement step by step.

### Step 1: Analyze the first statement
**Statement:** R and S configurations correspond to isomers of an optically active compound.

**Analysis:**
- R and S configurations refer to the stereochemical designations of chiral centers in molecules.
- An optically active compound is one that can rotate plane-polarized light, which typically occurs in chiral compounds.
- Therefore, R and S configurations do correspond to isomers (specifically enantiomers) of optically active compounds.

**Conclusion:** This statement is true.

### Step 2: Analyze the second statement
**Statement:** The process of converting an optically active compound into a racemic mixture is called racemization.

**Analysis:**
- Racemization is the process of converting an optically active compound (which has a specific rotation) into a racemic mixture (which has no net optical activity).
- This involves the formation of equal amounts of both enantiomers (R and S forms).
- Thus, this statement correctly describes the process.

**Conclusion:** This statement is true.

### Step 3: Analyze the third statement
**Statement:** A molecule containing a plane of symmetry can be optically active.

**Analysis:**
- A plane of symmetry in a molecule indicates that the molecule is symmetrical and can be divided into two mirror-image halves.
- Such symmetry typically results in the molecule being achiral (not chiral), meaning it cannot rotate plane-polarized light.
- Therefore, a molecule with a plane of symmetry cannot be optically active.

**Conclusion:** This statement is false.

### Step 4: Analyze the fourth statement
**Statement:** Optical isomers that are not enantiomers are called diastereomers.

**Analysis:**
- Diastereomers are stereoisomers that are not mirror images of each other, which means they do not have the same configuration at one or more (but not all) chiral centers.
- This statement correctly describes the relationship between optical isomers and diastereomers.

**Conclusion:** This statement is true.

### Final Conclusion
The false statement among the options is: **"A molecule containing a plane of symmetry can be optically active."**

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