Isomers

One chemist studying silver isocyanate, and another studying silver fulminate submitted their findings to a scientific journal whose editor realized that both compounds had the same number of atoms but vastly different properties because of their respective arrangement.
 Friedrich Wöhler and Justus von Liebig Germany 1823 Isomers

One chemist studying silver isocyanate, and another studying silver fulminate submitted their findings to a scientific journal whose editor realized that both compounds had the same number of atoms but vastly different properties because of their respective arrangement.