29.4.1—Enantiomers have identical physical/chemical

Enantiomers are non-superimposable mirror images. In an achiral environment they have the same melting point, boiling point and many chemical properties, but they rotate plane-polarised light in opposite directions.

A chiral receptor or enzyme is itself asymmetric, so the two enantiomers can bind differently and produce different biological effects.

Two enantiomers may pass through an ordinary solvent identically yet one fit a biological active site better, like opposite hands fitting a glove.

R and S labels do not by themselves tell you clockwise optical rotation, and “same formula” does not mean the molecules are superimposable.