What occurs during the inversion of configuration in a reaction?

Inversion of configuration refers to a specific change that occurs during a reaction when a chiral molecule is transformed into its enantiomer. This process typically occurs in reactions involving nucleophilic substitutions, such as the S_N2 mechanism, where the incoming nucleophile attacks the carbon atom from the opposite side of the leaving group. This leads to a complete switch in the spatial arrangement of the substituents around the carbon center.

When a chiral reactant undergoes inversion, the spatial arrangement of its substituents changes from one configuration to the opposite one. Therefore, the resulting product possesses an opposite configuration to that of the original reactant. This distinctive change is key in stereochemistry, where the difference between enantiomers can lead to different properties, including biological activity.

Other choices do not accurately reflect the nature of inversion of configuration. For example, if the product were to have the same configuration as the reactant, or if the configuration remained unchanged, it would not represent an inversion process at all. Additionally, stating that the reactant is not altered overlooks the essential transformation characteristic of such reactions.