Hi I'm a chemist, my current work is with PFAS compounds, often known as forever chemicals. Please ask me about those, or anything else you are curious about related to chemistry. I will try to give you a solid response.

    • AnarchoCynicalist [any]
      ·
      2 years ago

      Not op, but they don't seem to answer. It's because isomeres are not chemically identical. There are many different types of isomerism, but even the most plain one (mirror isomerism) results in materials with different properties. Imagine a key with its teeth on the wrong side being unable to unlock the same door.

      Then there is the phenomenon that isomeres in L-configuration are somehow slightly more stable than those in D-configuration, but you'd need to consult a physicist to figure out the reason for that mindfuck.

      • axont [she/her, comrade/them]
        ·
        2 years ago

        I was told in school that L enantiomers (I was taught to call them sinistral) are more stable than D-configuration because of less eclipsing of atoms with lone pairs. I don't remember why that would make it more stable though. That might have just been a specific compound. I slept a lot in class, sorry.

          • ZoomeristLeninist [they/them, she/her]M
            ·
            2 years ago

            S/R is typically used for chiral centers while L/D are used to describe whole molecules. so IUPAC names for large molecules with lots of chiral centers have a mess of R's and S's but can be simplified with a common name with an L or D. for example the IUPAC name for the biologically active glucose is (2R,3S,4R,5R)-2,3,4,5,6-Pentahydroxyhexanal, but it can be simplified to the common name D-glucose

          • StolenStalin [comrade/them,they/them]
            ·
            2 years ago

            R are more common because enzymes and protein folding are stereospecific. And they evolved along with us, the original microbes that won out just happened to make R instead of S in most places.