Refrachor (F) – seventy-year-old tool and a contemporary observation: estimation of equilibrium compositions of 1H- and 2H-tautomers of tetrazole and 1,2,3-triazole and imine–amine composition of acetaldimine–vinylamine tautomerism.

Refrachor with a symbol F a new physical constant proposed for the first time in 1951 by Joshi and Tuli defined by the equation F = –P log( n D 20 –1) where P is the parachor and n D 20 is the refractive index, is now used in our present work to calculate the percentage composition of 1H- and 2H-tautomers of tetrazole, 1,2,3-triazole, and imine-enamine tautomerism of acetaldimine in their equilibrium mixtures. [ABSTRACT FROM AUTHOR]