Chemistry - STEREO ISOMERISM Question with Solution | TestHub

The first Newman is 2-methylbutane, (CH₃)₂CH-CH₂CH₃; the second is n-pentane, CH₃CH₂CH₂CH₂CH₃. Both have molecular formula C₅H₁₂ but the carbon skeletons (chains of different lengths) differ - this is chain (nuclear) isomerism. It is not positional isomerism, which requires the same carbon skeleton with a group at different positions; not conformational (not interconvertible by rotation); and metamerism applies to compounds with heteroatoms like ethers.